diff --git a/ink-engine-runtime/StoryState.cs b/ink-engine-runtime/StoryState.cs
index 4639a494..727a3cac 100755
--- a/ink-engine-runtime/StoryState.cs
+++ b/ink-engine-runtime/StoryState.cs
@@ -810,6 +810,10 @@ internal void StartExternalFunctionEvaluation (Container funcContainer, params o
             callStack = new CallStack (funcContainer);
             callStack.currentElement.type = PushPopType.Function;
 
+            // Change the callstack the variableState is looking at to be
+            // this temporary function evaluation one. We'll restore it afterwards
+            variablesState.callStack = callStack;
+
             // By setting ourselves in external function evaluation mode,
             // we're saying it's okay to end the flow without a Done or End,
             // but with a ~ return instead.