diff --git a/source/games/duke/src/actors.cpp b/source/games/duke/src/actors.cpp
index 40d4711c5..5c91ba3b4 100644
--- a/source/games/duke/src/actors.cpp
+++ b/source/games/duke/src/actors.cpp
@@ -978,7 +978,7 @@ void movemasterswitch(DDukeActor *actor, int spectype1, int spectype2)
 		{
 			operatesectors(spri->sector(), actor);
 
-			DukeSectIterator it(spri->sectnum);
+			DukeSectIterator it(actor->sector());
 			while (auto effector = it.Next())
 			{
 				auto sj = effector->s;
@@ -2255,7 +2255,7 @@ bool jibs(DDukeActor *actor, int JIBS6, bool timeout, bool callsetsprite, bool f
 	if (callsetsprite) setsprite(actor, s->pos);
 
 	// this was after the slope calls, but we should avoid calling that for invalid sectors.
-	if (!validSectorIndex(s->sectnum))
+	if (!s->insector())
 	{
 		deletesprite(actor);
 		return false;
@@ -2451,7 +2451,7 @@ void shell(DDukeActor* actor, bool morecheck)
 
 	ssp(actor, CLIPMASK0);
 
-	if (s->sectnum < 0 || morecheck)
+	if (!s->insector() || morecheck)
 	{
 		deletesprite(actor);
 		return;
@@ -2506,7 +2506,7 @@ void glasspieces(DDukeActor* actor)
 	makeitfall(actor);
 
 	if (s->zvel > 4096) s->zvel = 4096;
-	if (s->sectnum < 0)
+	if (!s->insector())
 	{
 		deletesprite(actor);
 		return;
@@ -3006,7 +3006,7 @@ void handle_se14(DDukeActor* actor, bool checkstat, int RPG, int JIBS6)
 			auto Owner = actor->GetOwner();
 			if (Owner)
 			{
-				DukeSectIterator itr(Owner->s->sectnum);
+				DukeSectIterator itr(Owner->sector());
 				while (auto a2 = itr.Next())
 				{
 					if (a2->s->statnum == 1 && badguy(a2) && a2->s->picnum != SECTOREFFECTOR && a2->s->picnum != LOCATORS)
@@ -3174,7 +3174,7 @@ void handle_se30(DDukeActor *actor, int JIBS6)
 
 			if (Owner)
 			{
-				DukeSectIterator it(Owner->s->sectnum);
+				DukeSectIterator it(Owner->sector());
 				while (auto a2 = it.Next())
 				{
 					if (a2->s->statnum == 1 && badguy(a2) && a2->s->picnum != SECTOREFFECTOR && a2->s->picnum != LOCATORS)
@@ -3990,7 +3990,7 @@ void handle_se17(DDukeActor* actor)
 		if (act2 == nullptr) return;
 		auto spr2 = act2->s;
 
-		DukeSectIterator its(s->sectnum);
+		DukeSectIterator its(actor->sector());
 		while (auto act3 = its.Next())
 		{
 			auto spr3 = act3->s;
@@ -4065,7 +4065,7 @@ void handle_se18(DDukeActor *actor, bool morecheck)
 				sc->floorz += sc->extra;
 				if (morecheck)
 				{
-					DukeSectIterator it(actor->s->sectnum);
+					DukeSectIterator it(actor->sector());
 					while (auto a2 = it.Next())
 					{
 						if (a2->s->picnum == TILE_APLAYER && a2->GetOwner())
@@ -4102,7 +4102,7 @@ void handle_se18(DDukeActor *actor, bool morecheck)
 				sc->floorz -= sc->extra;
 				if (morecheck)
 				{
-					DukeSectIterator it(actor->s->sectnum);
+					DukeSectIterator it(actor->sector());
 					while (auto a2 = it.Next())
 					{
 						if (a2->s->picnum == TILE_APLAYER && a2->GetOwner())
@@ -4489,7 +4489,7 @@ void handle_se24(DDukeActor *actor, const int16_t *list1, const int16_t *list2,
 	int x = MulScale(actor->s->yvel, bcos(actor->s->ang), 18);
 	int l = MulScale(actor->s->yvel, bsin(actor->s->ang), 18);
 
-	DukeSectIterator it(actor->s->sectnum);
+	DukeSectIterator it(actor->sector());
 	while (auto a2 = it.Next())
 	{
 		auto s2 = a2->s;
diff --git a/source/games/duke/src/actors_d.cpp b/source/games/duke/src/actors_d.cpp
index 6fe20fd36..3d90956c6 100644
--- a/source/games/duke/src/actors_d.cpp
+++ b/source/games/duke/src/actors_d.cpp
@@ -1413,7 +1413,7 @@ void movestandables_d(void)
 	{
 		int picnum = act->s->picnum;
 
-		if (act->s->sectnum < 0)
+		if (!act->insector())
 		{
 			deletesprite(act);
 			continue;
@@ -1794,7 +1794,7 @@ static void weaponcommon_d(DDukeActor* proj)
 		if (FindDistance2D(s->x - proj->temp_actor->s->x, s->y - proj->temp_actor->s->y) < 256)
 			coll.setSprite(proj->temp_actor);
 
-	if (s->sectnum < 0)
+	if (!s->insector())
 	{
 		deletesprite(proj);
 		return;
@@ -1927,7 +1927,7 @@ void moveweapons_d(void)
 	DukeStatIterator it(STAT_PROJECTILE);
 	while (auto act = it.Next())
 	{
-		if (act->s->sectnum < 0)
+		if (!act->insector())
 		{
 			deletesprite(act);
 			continue;
@@ -2009,7 +2009,7 @@ void movetransports_d(void)
 		
 		if (act->temp_data[0] > 0) act->temp_data[0]--;
 		
-		DukeSectIterator itj(spr->sectnum);
+		DukeSectIterator itj(act->sector());
 		while (auto act2 = itj.Next()) 
 		{
 			auto spr2 = act2->s;
@@ -2757,7 +2757,7 @@ static void flamethrowerflame(DDukeActor *actor)
 	movesprite_ex(actor, MulScale(xvel, bcos(s->ang), 14),
 		MulScale(xvel, bsin(s->ang), 14), s->zvel, CLIPMASK1, coll);
 
-	if (s->sectnum < 0)
+	if (!s->insector())
 	{
 		deletesprite(actor);
 		return;
@@ -3268,7 +3268,7 @@ void moveexplosions_d(void)  // STATNUM 5
 	{
 		auto s = act->s;
 
-		if (s->sectnum < 0 || s->xrepeat == 0) 
+		if (!s->insector() || s->xrepeat == 0) 
 		{
 			deletesprite(act);
 			continue;
diff --git a/source/games/duke/src/actors_r.cpp b/source/games/duke/src/actors_r.cpp
index d1882b64b..602d7b972 100644
--- a/source/games/duke/src/actors_r.cpp
+++ b/source/games/duke/src/actors_r.cpp
@@ -986,7 +986,7 @@ void movestandables_r(void)
 	{
 		int picnum = act->s->picnum;
 
-		if (act->s->sectnum < 0)
+		if (!act->insector())
 		{
 			deletesprite(act);
 			continue;
@@ -1406,7 +1406,7 @@ static void weaponcommon_r(DDukeActor *proj)
 		if (FindDistance2D(s->x - proj->temp_actor->s->x, s->y - proj->temp_actor->s->y) < 256)
 			coll.setSprite(proj->temp_actor);
 
-	if (s->sectnum < 0) // || (isRR() && s->sector()->filler == 800))
+	if (!s->insector()) // || (isRR() && s->sector()->filler == 800))
 	{
 		deletesprite(proj);
 		return;
@@ -1504,7 +1504,7 @@ void moveweapons_r(void)
 	DukeStatIterator it(STAT_PROJECTILE);
 	while (auto proj = it.Next())
 	{
-		if (proj->s->sectnum < 0)
+		if (!proj->insector())
 		{
 			deletesprite(proj);
 			continue;
@@ -2854,7 +2854,7 @@ void moveactors_r(void)
 		auto s = act->s;
 		bool deleteafterexecute = false;	// taking a cue here from RedNukem to not run scripts on deleted sprites.
 
-		if( s->xrepeat == 0 || !validSectorIndex(s->sectnum))
+		if( s->xrepeat == 0 || !s->insector())
 		{
 			deletesprite(act);
 			continue;
@@ -3124,7 +3124,7 @@ void moveexplosions_r(void)  // STATNUM 5
 		t = &act->temp_data[0];
 		auto sectp = s->sector();
 
-		if (s->sectnum < 0 || s->xrepeat == 0) 
+		if (!s->insector() || s->xrepeat == 0) 
 		{
 			deletesprite(act);
 			continue;
diff --git a/source/games/duke/src/animatesprites_r.cpp b/source/games/duke/src/animatesprites_r.cpp
index 83a2ce58c..12c8fe49d 100644
--- a/source/games/duke/src/animatesprites_r.cpp
+++ b/source/games/duke/src/animatesprites_r.cpp
@@ -164,7 +164,6 @@ void animatesprites_r(spritetype* tsprite, int& spritesortcnt, int x, int y, int
 			t->pos = s->interpolatedvec3(smoothratio);
 		}
 
-		//sect = s->sectnum;
 		auto sectp = s->sector();
 		t1 = h->temp_data[1];
 		t3 = h->temp_data[3];
diff --git a/source/games/duke/src/gameexec.cpp b/source/games/duke/src/gameexec.cpp
index 9f89f3302..da49b00a7 100644
--- a/source/games/duke/src/gameexec.cpp
+++ b/source/games/duke/src/gameexec.cpp
@@ -2113,7 +2113,7 @@ int ParseState::parse(void)
 		break;
 	case concmd_spawn:
 		insptr++;
-		if(validSectorIndex(g_sp->sectnum))
+		if(g_ac->insector())
 			spawn(g_ac,*insptr);
 		insptr++;
 		break;
@@ -2147,7 +2147,7 @@ int ParseState::parse(void)
 			insptr++;
 			bool weap = fi.spawnweapondebris(g_sp->picnum, dnum);
 
-			if(validSectorIndex(g_sp->sectnum))
+			if(g_ac->insector())
 				for(j=(*insptr)-1;j>=0;j--)
 			{
 				if(weap)
@@ -2858,7 +2858,7 @@ int ParseState::parse(void)
 
 		lIn = *insptr++;
 		lIn = GetGameVarID(lIn, g_ac, g_p);
-		if(validSectorIndex(g_sp->sectnum))
+		if(g_ac->insector())
 			lReturn = spawn(g_ac, lIn);
 
 		SetGameVarID(g_iReturnVarID, ActorToScriptIndex(lReturn), g_ac, g_p);
@@ -2868,7 +2868,7 @@ int ParseState::parse(void)
 	{
 		DDukeActor* lReturn = nullptr;
 		insptr++;
-		if(validSectorIndex(g_sp->sectnum))
+		if(g_ac->insector())
 			lReturn = spawn(g_ac, *insptr);
 		insptr++;
 		SetGameVarID(g_iReturnVarID, ActorToScriptIndex(lReturn), g_ac, g_p);
@@ -3668,7 +3668,7 @@ void LoadActor(DDukeActor *actor, int p, int x)
 
 	s.killit_flag = 0;
 
-	if(!validSectorIndex(actor->s->sectnum))
+	if(!actor->insector())
 	{
 		deletesprite(actor);
 		return;
@@ -3757,7 +3757,7 @@ void execute(DDukeActor *actor,int p,int x)
 
 	s.killit_flag = 0;
 
-	if(!validSectorIndex(actor->s->sectnum))
+	if(!actor->insector())
 	{
 		if(badguy(actor))
 			ps[p].actors_killed++;
diff --git a/source/games/duke/src/sectors_d.cpp b/source/games/duke/src/sectors_d.cpp
index 53ec5e99e..11154cd5e 100644
--- a/source/games/duke/src/sectors_d.cpp
+++ b/source/games/duke/src/sectors_d.cpp
@@ -1824,7 +1824,7 @@ void checksectors_d(int snum)
 		{
 			if (isanunderoperator(p->GetActor()->sector()->lotag))
 			{
-				DukeSectIterator it(p->GetActor()->s->sectnum);
+				DukeSectIterator it(p->GetActor()->sector());
 				while (auto act = it.Next())
 				{
 					if (act->s->picnum == ACTIVATOR || act->s->picnum == MASTERSWITCH) return;
diff --git a/source/games/duke/src/sectors_r.cpp b/source/games/duke/src/sectors_r.cpp
index 2bfd313ee..6820feb9f 100644
--- a/source/games/duke/src/sectors_r.cpp
+++ b/source/games/duke/src/sectors_r.cpp
@@ -2774,7 +2774,7 @@ void checksectors_r(int snum)
 		{
 			if (isanunderoperator(p->GetActor()->sector()->lotag))
 			{
-				DukeSectIterator it(p->GetActor()->s->sectnum);
+				DukeSectIterator it(p->GetActor()->sector());
 				while (auto act = it.Next())
 				{
 					if (act->s->picnum == ACTIVATOR || act->s->picnum == MASTERSWITCH)