Lauren urges Simon to relax after a stressful Dublin trip. While a few London singers sparkle, something is missing — until one teen steps up to the mic.

Nervous hopefuls wait for a life-changing phone call as Simon struggles with his decision. Later, crushing news forces him to look inside his heart.

After the field narrows to 16, the boys arrive in Miami for vocal coaching. Their harmonies give Simon goosebumps, but four singers just aren't ready.