diff --git a/common/space_lua/stdlib.ts b/common/space_lua/stdlib.ts
index ca3d0ee3..a993f7fd 100644
--- a/common/space_lua/stdlib.ts
+++ b/common/space_lua/stdlib.ts
@@ -124,7 +124,10 @@ const xpcallFunction = new LuaBuiltinFunction(
 );
 
 const setmetatableFunction = new LuaBuiltinFunction(
-  (_sf, table: LuaTable, metatable: LuaTable) => {
+  (sf, table: LuaTable, metatable: LuaTable) => {
+    if (!metatable) {
+      throw new LuaRuntimeError("metatable cannot be set to nil", sf);
+    }
     table.metatable = metatable;
     return table;
   },