1 files changed, 2 insertions, 0 deletions
diff --git a/engines/sci/engine/script.cpp b/engines/sci/engine/script.cpp
index 25bf91c3ad..0592940559 100644
--- a/engines/sci/engine/script.cpp
+++ b/engines/sci/engine/script.cpp
@@ -383,6 +383,7 @@ void Script::relocateSci3(reg_t block) {
 }
 
 void Script::incrementLockers() {
+	assert(!_markedAsDeleted);
 	_lockers++;
 }
 
@@ -396,6 +397,7 @@ int Script::getLockers() const {
 }
 
 void Script::setLockers(int lockers) {
+	assert(lockers == 0 || !_markedAsDeleted);
 	_lockers = lockers;
 }