diff --git a/01 - JavaScript Drum Kit/index-START.html b/01 - JavaScript Drum Kit/index-START.html
index 4070d32767..a6324c3506 100644
--- a/01 - JavaScript Drum Kit/index-START.html	
+++ b/01 - JavaScript Drum Kit/index-START.html	
@@ -59,6 +59,30 @@
 
 <script>
 
+  function playSound(e) {
+    const audio = document.querySelector(`audio[data-key="${e.keyCode}"]`);
+    if (!audio) return; // Stop function from running
+
+    const key = document.querySelector(`div[data-key="${e.keyCode}"]`);
+
+    key.classList.add("playing");
+
+    audio.currentTime = 0; // Rewind
+    audio.play();
+  }
+
+
+  function removeTransition(e) {
+    if (e.propertyName !== 'transform') return;
+
+    this.classList.remove("playing");
+  }
+
+
+  const keys = document.querySelectorAll(".key");
+  keys.forEach(key => key.addEventListener('transitionend', removeTransition));
+  window.addEventListener('keydown', playSound);
+
 </script>