diff --git a/apps/openmw/mwlua/localscripts.cpp b/apps/openmw/mwlua/localscripts.cpp
index 883afb5328..e3e46d453f 100644
--- a/apps/openmw/mwlua/localscripts.cpp
+++ b/apps/openmw/mwlua/localscripts.cpp
@@ -198,7 +198,7 @@ namespace MWLua
     }
 
     LocalScripts::LocalScripts(LuaUtil::LuaState* lua, const LObject& obj)
-        : LuaUtil::ScriptsContainer(lua, "L" + idToString(obj.id()))
+        : LuaUtil::ScriptsContainer(lua, "L" + obj.id().toString())
         , mData(obj)
     {
         this->addPackage("openmw.self", sol::make_object(lua->sol(), &mData));
diff --git a/apps/openmw/mwlua/luamanagerimp.cpp b/apps/openmw/mwlua/luamanagerimp.cpp
index 9bbd63ac25..6ab9a27581 100644
--- a/apps/openmw/mwlua/luamanagerimp.cpp
+++ b/apps/openmw/mwlua/luamanagerimp.cpp
@@ -187,11 +187,12 @@ namespace MWLua
         for (LocalEvent& e : localEvents)
         {
             LObject obj(e.mDest);
-            LocalScripts* scripts = obj.isValid() ? obj.ptr().getRefData().getLuaScripts() : nullptr;
+            const MWWorld::Ptr& ptr = obj.ptrOrNull();
+            LocalScripts* scripts = ptr.isEmpty() ? nullptr : ptr.getRefData().getLuaScripts();
             if (scripts)
                 scripts->receiveEvent(e.mEventName, e.mEventData);
             else
-                Log(Debug::Debug) << "Ignored event " << e.mEventName << " to L" << idToString(e.mDest)
+                Log(Debug::Debug) << "Ignored event " << e.mEventName << " to L" << e.mDest.toString()
                                   << ". Object not found or has no attached scripts";
         }
 
@@ -204,14 +205,15 @@ namespace MWLua
         for (const LocalEngineEvent& e : mLocalEngineEvents)
         {
             LObject obj(e.mDest);
-            if (!obj.isValid())
+            const MWWorld::Ptr& ptr = obj.ptrOrNull();
+            if (ptr.isEmpty())
             {
                 if (luaDebug)
-                    Log(Debug::Verbose) << "Can not call engine handlers: object" << idToString(e.mDest)
+                    Log(Debug::Verbose) << "Can not call engine handlers: object" << e.mDest.toString()
                                         << " is not found";
                 continue;
             }
-            LocalScripts* scripts = obj.ptr().getRefData().getLuaScripts();
+            LocalScripts* scripts = ptr.getRefData().getLuaScripts();
             if (scripts)
                 scripts->receiveEngineEvent(e.mEvent);
         }
@@ -238,17 +240,18 @@ namespace MWLua
         for (ObjectId id : mObjectAddedEvents)
         {
             GObject obj(id);
-            if (obj.isValid())
+            const MWWorld::Ptr& ptr = obj.ptrOrNull();
+            if (!ptr.isEmpty())
             {
                 mGlobalScripts.objectActive(obj);
-                const MWWorld::Class& objClass = obj.ptr().getClass();
+                const MWWorld::Class& objClass = ptr.getClass();
                 if (objClass.isActor())
                     mGlobalScripts.actorActive(obj);
-                if (mWorldView.isItem(obj.ptr()))
+                if (mWorldView.isItem(ptr))
                     mGlobalScripts.itemActive(obj);
             }
             else if (luaDebug)
-                Log(Debug::Verbose) << "Could not resolve a Lua object added event: object" << idToString(id)
+                Log(Debug::Verbose) << "Could not resolve a Lua object added event: object" << id.toString()
                                     << " is already removed";
         }
         mObjectAddedEvents.clear();
@@ -675,7 +678,7 @@ namespace MWLua
             selectedScripts = selectedPtr.getRefData().getLuaScripts();
             if (selectedScripts)
                 selectedScripts->collectStats(selectedStats);
-            out << "Profiled object (selected in the in-game console): " << ptrToString(selectedPtr) << "\n";
+            out << "Profiled object (selected in the in-game console): " << selectedPtr.toString() << "\n";
         }
         else
             out << "No selected object. Use the in-game console to select an object for detailed profile.\n";
diff --git a/apps/openmw/mwlua/object.cpp b/apps/openmw/mwlua/object.cpp
deleted file mode 100644
index ed1a9dd9ec..0000000000
--- a/apps/openmw/mwlua/object.cpp
+++ /dev/null
@@ -1,59 +0,0 @@
-#include "object.hpp"
-
-#include "types/types.hpp"
-
-#include <components/misc/resourcehelpers.hpp>
-
-namespace MWLua
-{
-
-    std::string idToString(const ObjectId& id)
-    {
-        return std::to_string(id.mIndex) + "_" + std::to_string(id.mContentFile);
-    }
-
-    bool isMarker(const MWWorld::Ptr& ptr)
-    {
-        return Misc::ResourceHelpers::isHiddenMarker(ptr.getCellRef().getRefId());
-    }
-
-    std::string ptrToString(const MWWorld::Ptr& ptr)
-    {
-        std::string res = "object";
-        if (ptr.getRefData().isDeleted())
-            res = "deleted object";
-        res.append(idToString(getId(ptr)));
-        res.append(" (");
-        res.append(getLuaObjectTypeName(ptr));
-        res.append(", ");
-        res.append(ptr.getCellRef().getRefId().getRefIdString());
-        res.append(")");
-        return res;
-    }
-
-    std::string Object::toString() const
-    {
-        if (isValid())
-            return ptrToString(ptr());
-        else
-            return "object" + idToString(mId) + " (not found)";
-    }
-
-    bool Object::isValid() const
-    {
-        MWWorld::WorldModel& w = *MWBase::Environment::get().getWorldModel();
-        if (mLastUpdate < w.getPtrIndexUpdateCounter())
-        {
-            mPtr = w.getPtr(mId);
-            mLastUpdate = w.getPtrIndexUpdateCounter();
-        }
-        return !mPtr.isEmpty();
-    }
-
-    const MWWorld::Ptr& Object::ptr() const
-    {
-        if (!isValid())
-            throw std::runtime_error("Object is not available: " + idToString(mId));
-        return mPtr;
-    }
-}
diff --git a/apps/openmw/mwlua/object.hpp b/apps/openmw/mwlua/object.hpp
index 9c720c67ce..9f4075582a 100644
--- a/apps/openmw/mwlua/object.hpp
+++ b/apps/openmw/mwlua/object.hpp
@@ -21,39 +21,24 @@ namespace MWLua
     {
         return ptr.getCellRef().getRefNum();
     }
-    std::string idToString(const ObjectId& id);
-    std::string ptrToString(const MWWorld::Ptr& ptr);
-    bool isMarker(const MWWorld::Ptr& ptr);
 
     // Lua scripts can't use MWWorld::Ptr directly, because lifetime of a script can be longer than lifetime of Ptr.
     // `GObject` and `LObject` are intended to be passed to Lua as a userdata.
     // It automatically updates the underlying Ptr when needed.
-    class Object
+    class Object : public MWWorld::SafePtr
     {
     public:
-        Object(ObjectId id)
-            : mId(id)
-        {
-        }
-        virtual ~Object() {}
-        ObjectId id() const { return mId; }
-
-        std::string toString() const;
-
-        // Updates and returns the underlying Ptr. Throws an exception if object is not available.
-        const MWWorld::Ptr& ptr() const;
-
-        // Returns `true` if calling `ptr()` is safe.
-        bool isValid() const;
-
-        virtual sol::object getObject(lua_State* lua, ObjectId id) const = 0; // returns LObject or GOBject
+        using SafePtr::SafePtr;
+        virtual sol::object getObject(lua_State* lua, ObjectId id) const = 0; // returns LObject or GObject
         virtual sol::object getCell(lua_State* lua, MWWorld::CellStore* store) const = 0; // returns LCell or GCell
 
-    protected:
-        const ObjectId mId;
-
-        mutable MWWorld::Ptr mPtr;
-        mutable size_t mLastUpdate = 0;
+        const MWWorld::Ptr& ptr() const
+        {
+            const MWWorld::Ptr& res = ptrOrNull();
+            if (res.isEmpty())
+                throw std::runtime_error("Object is not available: " + id().toString());
+            return res;
+        }
     };
 
     // Used only in local scripts
@@ -100,7 +85,6 @@ namespace MWLua
     {
         Obj mObj;
     };
-
 }
 
 #endif // MWLUA_OBJECT_H
diff --git a/apps/openmw/mwlua/objectbindings.cpp b/apps/openmw/mwlua/objectbindings.cpp
index 5b67b9f718..f92906f54e 100644
--- a/apps/openmw/mwlua/objectbindings.cpp
+++ b/apps/openmw/mwlua/objectbindings.cpp
@@ -116,10 +116,10 @@ namespace MWLua
             {
                 MWWorld::Ptr object = MWBase::Environment::get().getWorldModel()->getPtr(mObject);
                 if (object.isEmpty())
-                    throw std::runtime_error(std::string("Object not found: " + idToString(mObject)));
+                    throw std::runtime_error(std::string("Object not found: " + mObject.toString()));
                 MWWorld::Ptr actor = MWBase::Environment::get().getWorldModel()->getPtr(mActor);
                 if (actor.isEmpty())
-                    throw std::runtime_error(std::string("Actor not found: " + idToString(mActor)));
+                    throw std::runtime_error(std::string("Actor not found: " + mActor.toString()));
 
                 if (object.getRefData().activate())
                 {
@@ -131,8 +131,8 @@ namespace MWLua
 
             std::string toString() const override
             {
-                return std::string("ActivateAction object=") + idToString(mObject) + std::string(" actor=")
-                    + idToString(mActor);
+                return std::string("ActivateAction object=") + mObject.toString() + std::string(" actor=")
+                    + mActor.toString();
             }
 
         private:
@@ -165,7 +165,7 @@ namespace MWLua
         template <class ObjectT>
         void addBasicBindings(sol::usertype<ObjectT>& objectT, const Context& context)
         {
-            objectT["isValid"] = [](const ObjectT& o) { return o.isValid(); };
+            objectT["isValid"] = [](const ObjectT& o) { return !o.ptrOrNull().isEmpty(); };
             objectT["recordId"] = sol::readonly_property(
                 [](const ObjectT& o) -> std::string { return o.ptr().getCellRef().getRefId().getRefIdString(); });
             objectT["cell"] = sol::readonly_property([](const ObjectT& o) -> sol::optional<Cell<ObjectT>> {
@@ -197,7 +197,7 @@ namespace MWLua
                 if (esmRecordType != ESM::REC_CREA && esmRecordType != ESM::REC_NPC_)
                     throw std::runtime_error(
                         "The argument of `activateBy` must be an actor who activates the object. Got: "
-                        + ptrToString(actor.ptr()));
+                        + actor.toString());
                 context.mLuaManager->addAction(std::make_unique<ActivateAction>(context.mLua, o.id(), actor.id()));
             };
 
@@ -266,7 +266,7 @@ namespace MWLua
                     MWWorld::Ptr ptr = object.ptr();
                     LocalScripts* localScripts = ptr.getRefData().getLuaScripts();
                     if (!localScripts || !localScripts->hasScript(*scriptId))
-                        throw std::runtime_error("There is no script " + std::string(path) + " on " + ptrToString(ptr));
+                        throw std::runtime_error("There is no script " + std::string(path) + " on " + ptr.toString());
                     if (localScripts->getAutoStartConf().count(*scriptId) > 0)
                         throw std::runtime_error("Autostarted script can not be removed: " + std::string(path));
                     localScripts->removeScript(*scriptId);
diff --git a/apps/openmw/mwlua/types/actor.cpp b/apps/openmw/mwlua/types/actor.cpp
index 10634d1812..97d797d8d5 100644
--- a/apps/openmw/mwlua/types/actor.cpp
+++ b/apps/openmw/mwlua/types/actor.cpp
@@ -51,7 +51,7 @@ namespace MWLua
                             || itemPtr.getContainerStore() != static_cast<const MWWorld::ContainerStore*>(&store))
                         {
                             Log(Debug::Warning)
-                                << "Object" << idToString(std::get<ObjectId>(item)) << " is not in inventory";
+                                << "Object" << std::get<ObjectId>(item).toString() << " is not in inventory";
                             return false;
                         }
                     }
@@ -77,7 +77,7 @@ namespace MWLua
                             allowedSlots.begin(), allowedSlots.end(), [&](int s) { return !usedSlots[s]; });
                         if (firstAllowed == allowedSlots.end())
                         {
-                            Log(Debug::Warning) << "No suitable slot for " << ptrToString(itemPtr);
+                            Log(Debug::Warning) << "No suitable slot for " << itemPtr.toString();
                             return false;
                         }
                         slot = *firstAllowed;
@@ -261,7 +261,7 @@ namespace MWLua
             if (!obj.ptr().getClass().hasInventoryStore(obj.ptr()))
             {
                 if (!equipment.empty())
-                    throw std::runtime_error(ptrToString(obj.ptr()) + " has no equipment slots");
+                    throw std::runtime_error(obj.toString() + " has no equipment slots");
                 return;
             }
             SetEquipmentAction::Equipment eqp;
diff --git a/apps/openmw/mwlua/types/types.cpp b/apps/openmw/mwlua/types/types.cpp
index 2ac72e710e..75cc072ce2 100644
--- a/apps/openmw/mwlua/types/types.cpp
+++ b/apps/openmw/mwlua/types/types.cpp
@@ -95,7 +95,7 @@ namespace MWLua
             std::string msg = "Requires type '";
             msg.append(getLuaObjectTypeName(recordType));
             msg.append("', but applied to ");
-            msg.append(ptrToString(ptr));
+            msg.append(ptr.toString());
             throw std::runtime_error(msg);
         }
         return ptr;
diff --git a/apps/openmw/mwlua/worldview.cpp b/apps/openmw/mwlua/worldview.cpp
index cc1d381531..d06420399b 100644
--- a/apps/openmw/mwlua/worldview.cpp
+++ b/apps/openmw/mwlua/worldview.cpp
@@ -4,6 +4,8 @@
 #include <components/esm3/esmwriter.hpp>
 #include <components/esm3/loadcell.hpp>
 
+#include <components/misc/resourcehelpers.hpp>
+
 #include "../mwbase/windowmanager.hpp"
 
 #include "../mwclass/container.hpp"
@@ -39,7 +41,7 @@ namespace MWLua
     {
         // It is important to check `isMarker` first.
         // For example "prisonmarker" has class "Door" despite that it is only an invisible marker.
-        if (isMarker(ptr))
+        if (Misc::ResourceHelpers::isHiddenMarker(ptr.getCellRef().getRefId()))
             return nullptr;
         const MWWorld::Class& cls = ptr.getClass();
         if (cls.isActivator())
diff --git a/apps/openmw/mwworld/ptr.cpp b/apps/openmw/mwworld/ptr.cpp
new file mode 100644
index 0000000000..6ad6f143af
--- /dev/null
+++ b/apps/openmw/mwworld/ptr.cpp
@@ -0,0 +1,42 @@
+#include "ptr.hpp"
+
+#include "apps/openmw/mwbase/environment.hpp"
+
+#include "worldmodel.hpp"
+
+namespace MWWorld
+{
+
+    std::string Ptr::toString() const
+    {
+        std::string res = "object";
+        if (getRefData().isDeleted())
+            res = "deleted object";
+        res.append(getCellRef().getRefNum().toString());
+        res.append(" (");
+        res.append(getTypeDescription());
+        res.append(", ");
+        res.append(getCellRef().getRefId().getRefIdString());
+        res.append(")");
+        return res;
+    }
+
+    std::string SafePtr::toString() const
+    {
+        update();
+        if (mPtr.isEmpty())
+            return "object" + mId.toString() + " (not found)";
+        else
+            return mPtr.toString();
+    }
+
+    void SafePtr::update() const
+    {
+        WorldModel& w = *MWBase::Environment::get().getWorldModel();
+        if (mLastUpdate < w.getPtrIndexUpdateCounter())
+        {
+            mPtr = w.getPtr(mId);
+            mLastUpdate = w.getPtrIndexUpdateCounter();
+        }
+    }
+}
diff --git a/apps/openmw/mwworld/ptr.hpp b/apps/openmw/mwworld/ptr.hpp
index fdf69b8818..4299130aa8 100644
--- a/apps/openmw/mwworld/ptr.hpp
+++ b/apps/openmw/mwworld/ptr.hpp
@@ -128,6 +128,8 @@ namespace MWWorld
             : PtrBase(liveCellRef, cell, nullptr)
         {
         }
+
+        std::string toString() const;
     };
 
     /// @note The difference between Ptr and ConstPtr is that the second one adds const to the underlying pointers.
@@ -145,6 +147,41 @@ namespace MWWorld
         }
     };
 
+    // SafePtr holds Ptr and automatically updates it via WorldModel if the Ptr becomes invalid.
+    // Uses ESM::RefNum as an unique id. Can not be used for Ptrs without RefNum.
+    // Note: WorldModel automatically assignes RefNum to all registered Ptrs.
+    class SafePtr
+    {
+    public:
+        using Id = ESM::RefNum;
+
+        explicit SafePtr(Id id)
+            : mId(id)
+        {
+        }
+        explicit SafePtr(const Ptr& ptr)
+            : SafePtr(ptr.getCellRef().getRefNum())
+        {
+        }
+        virtual ~SafePtr() = default;
+        Id id() const { return mId; }
+
+        std::string toString() const;
+
+        const Ptr& ptrOrNull() const
+        {
+            update();
+            return mPtr;
+        }
+
+    private:
+        const Id mId;
+
+        mutable Ptr mPtr;
+        mutable size_t mLastUpdate = 0;
+
+        void update() const;
+    };
 }
 
 #endif
diff --git a/components/esm3/cellref.cpp b/components/esm3/cellref.cpp
index d9cef58a4b..d765497948 100644
--- a/components/esm3/cellref.cpp
+++ b/components/esm3/cellref.cpp
@@ -175,6 +175,11 @@ namespace ESM
         }
     }
 
+    std::string RefNum::toString() const
+    {
+        return std::to_string(mIndex) + "_" + std::to_string(mContentFile);
+    }
+
     void CellRef::load(ESMReader& esm, bool& isDeleted, bool wideRefNum)
     {
         loadId(esm, wideRefNum);
diff --git a/components/esm3/cellref.hpp b/components/esm3/cellref.hpp
index 7912c11b69..0ea118178f 100644
--- a/components/esm3/cellref.hpp
+++ b/components/esm3/cellref.hpp
@@ -27,6 +27,8 @@ namespace ESM
         inline bool hasContentFile() const { return mContentFile >= 0; }
 
         inline bool isSet() const { return mIndex != 0 || mContentFile != -1; }
+
+        std::string toString() const;
     };
 
     /* Cell reference. This represents ONE object (of many) inside the