diff --git a/kiss/src/kiss/SpecialForms.hx b/kiss/src/kiss/SpecialForms.hx
index 4129cba3..009dd519 100644
--- a/kiss/src/kiss/SpecialForms.hx
+++ b/kiss/src/kiss/SpecialForms.hx
@@ -220,8 +220,9 @@ class SpecialForms {
         };
 
         map["return"] = (wholeExp:ReaderExp, args:Array<ReaderExp>, k:KissState) -> {
-            wholeExp.checkNumArgs(1, 1, '(return [value])');
-            EReturn(k.convert(args[0])).withMacroPosOf(wholeExp);
+            wholeExp.checkNumArgs(0, 1, '(return [?value])');
+            var returnExpr = if (args.length == 1) k.convert(args[0]) else null;
+            EReturn(returnExpr).withMacroPosOf(wholeExp);
         };
 
         map["break"] = (wholeExp:ReaderExp, args:Array<ReaderExp>, k:KissState) -> {