diff --git a/src/13-catch-blocks.solution.1.ts b/src/13-catch-blocks.solution.4.ts
similarity index 72%
rename from src/13-catch-blocks.solution.1.ts
rename to src/13-catch-blocks.solution.4.ts
index 0a1723e6..ca11b533 100644
--- a/src/13-catch-blocks.solution.1.ts
+++ b/src/13-catch-blocks.solution.4.ts
@@ -5,8 +5,12 @@ const tryCatchDemo = (state: "fail" | "succeed") => {
     if (state === "fail") {
       throw new Error("Failure!");
     }
-  } catch (e: any) {
-    return e.message;
+  } catch (e: unknown) {
+    if (e instanceof Error) {
+      return e.message;
+    }
+
+    return 'Failure!';
   }
 };