diff --git a/src/macros/interface.rs b/src/macros/interface.rs
index 0b99480c..f9c64ef3 100644
--- a/src/macros/interface.rs
+++ b/src/macros/interface.rs
@@ -244,7 +244,7 @@ macro_rules! graphql_interface {
             }
         )*
 
-        panic!("Concrete type not handled by instance resolvers on {}", $outname);
+        return Ok($crate::Value::null());
     };
 
     ( @resolve_into_type, $buildargs:tt, ) => {