diff --git a/01 - JavaScript Drum Kit/index-START.html b/01 - JavaScript Drum Kit/index-START.html
index 4070d32767..1a16d0997c 100644
--- a/01 - JavaScript Drum Kit/index-START.html	
+++ b/01 - JavaScript Drum Kit/index-START.html	
@@ -58,7 +58,24 @@
   <audio data-key="76" src="sounds/tink.wav"></audio>
 
 <script>
+  function removeTransition(e) {
+    if (e.propertyName !== 'transform') return;
+    e.target.classList.remove('playing');
+  }
 
+  function playSound(e) {
+    const audio = document.querySelector(`audio[data-key="${e.keyCode}"]`);
+    const key = document.querySelector(`div[data-key="${e.keyCode}"]`);
+    if (!audio) return;
+
+    key.classList.add('playing');
+    audio.currentTime = 0;
+    audio.play();
+  }
+
+  const keys = Array.from(document.querySelectorAll('.key'));
+  keys.forEach(key => key.addEventListener('transitionend', removeTransition));
+  window.addEventListener('keydown', playSound);
 </script>