Footage show Bill Murray and Jon Hamm take the to stage to sing at an after-party following SNL's "crazy" 50th anniversary celebrations.<br /><br />A swarm of A-listers attended the Saturday Night Live 50th anniversary spectacular - including Meryl Streep, Lady Gaga and Sabrina Carpenter.<br /><br />After the anniversary show finished, celebrities headed to The Plaza Hotel in New York City for an after-party.
