diff --git a/cryptography/README.md b/cryptography/README.md
index 49da1e5..70e8836 100644
--- a/cryptography/README.md
+++ b/cryptography/README.md
@@ -334,7 +334,7 @@ Future<void> main() async {
     keyPair: aliceKeyPair,
     remotePublicKey: bobPublicKey,
   );
-  final sharedSecretBytes = await aliceKeyPair.extractBytes();
+  final sharedSecretBytes = await sharedSecret.extractBytes();
   print('Shared secret: $sharedSecretBytes');
 }
 ```
@@ -435,4 +435,4 @@ Future<void> main() async {
 
   print('SHA-512 hash: ${hash.bytes}');
 }
-```
\ No newline at end of file
+```