diff --git a/source/blood/src/loadsave.cpp b/source/blood/src/loadsave.cpp
index 5284a4182..2364c2feb 100644
--- a/source/blood/src/loadsave.cpp
+++ b/source/blood/src/loadsave.cpp
@@ -451,8 +451,8 @@ void UnindexAIState(AISTATE*& state)
     auto index = intptr_t(state);
     if (index >= 0 && index < countof(allAIStates))
     {
-		Printf("Unindexing %i to state %p\n", int(index), state);
         state = allAIStates[index];
+        Printf("Unindexing %i to state %p\n", int(index), state);
     }
 	else
 	{
diff --git a/source/sw/src/ai.cpp b/source/sw/src/ai.cpp
index 5f5cac9fe..c2e9fc226 100644
--- a/source/sw/src/ai.cpp
+++ b/source/sw/src/ai.cpp
@@ -305,12 +305,10 @@ CanSeePlayer(short SpriteNum)
     // if actor can still see the player
     int look_height = SPRITEp_TOS(sp);
 
-    ASSERT(u->tgt_sp);
-
     //if (FAF_Sector(sp->sectnum))
     //    return(TRUE);
 
-    if (FAFcansee(sp->x, sp->y, look_height, sp->sectnum, u->tgt_sp->x, u->tgt_sp->y, SPRITEp_UPPER(u->tgt_sp), u->tgt_sp->sectnum))
+    if (u->tgt_sp && FAFcansee(sp->x, sp->y, look_height, sp->sectnum, u->tgt_sp->x, u->tgt_sp->y, SPRITEp_UPPER(u->tgt_sp), u->tgt_sp->sectnum))
         return TRUE;
     else
         return FALSE;
@@ -644,6 +642,12 @@ DoActorActionDecide(short SpriteNum)
     u->Dist = 0;
     action = InitActorDecide;
 
+    // target is gone.
+    if (u->tgt_sp == nullptr)
+    {
+        return action;
+    }
+
     if (TEST(u->Flags, SPR_JUMPING | SPR_FALLING))
     {
         //CON_Message("Jumping or falling");
@@ -658,7 +662,6 @@ DoActorActionDecide(short SpriteNum)
         return action;
     }
 
-
     ICanSee = CanSeePlayer(SpriteNum);  // Only need to call once
     // But need the result multiple times
 
@@ -845,6 +848,9 @@ DoActorDecide(short SpriteNum)
     if (actor_action == InitActorAttack && u->WeaponNum == 0)
         return 0;   // Just let the actor do as it was doing before in this case
 
+    // Target is gone.
+    if (u->tgt_sp == nullptr)
+        return 0;
 
     // zombie is attacking a player
     if (actor_action == InitActorAttack && u->ID == ZOMBIE_RUN_R0 && User[u->tgt_sp-sprite]->PlayerP)
diff --git a/source/sw/src/sprite.cpp b/source/sw/src/sprite.cpp
index 9b8d27f40..281abc783 100644
--- a/source/sw/src/sprite.cpp
+++ b/source/sw/src/sprite.cpp
@@ -812,6 +812,17 @@ KillSprite(int16_t SpriteNum)
     memset(sp, 0xCC, sizeof(SPRITE));
     sp->statnum = statnum;
     sp->sectnum = sectnum;
+
+    // Kill references in all users - slow but unavoidable if we don't want the game to crash on stale pointers.
+    for (auto u : User)
+    {
+        if (u)
+        {
+            if (u->hi_sp == sp) u->hi_sp = nullptr;
+            if (u->lo_sp == sp) u->lo_sp = nullptr;
+            if (u->tgt_sp == sp) u->tgt_sp = nullptr;
+        }
+    }
 }
 
 void ChangeState(short SpriteNum, STATEp statep)