diff --git a/source/day_02/mod.rs b/source/day_02/mod.rs
index 7ce5bac..f679c31 100644
--- a/source/day_02/mod.rs
+++ b/source/day_02/mod.rs
@@ -36,7 +36,7 @@ impl FromStr for Command {
       "forward" => Ok(Self::Forward(amount)),
       "down" => Ok(Self::Down(amount)),
       "up" => Ok(Self::Up(amount)),
-      _ => unimplemented!(),
+      _ => Err(eyre!("Unknown command: {}", s)),
     }
   }
 }