When Kevin Spacey [1] stopped by The Tonight Show Starring Jimmy Fallon in November, he and Jimmy Fallon went back and forth with celebrity impressions, and Kevin's hilarious takes on people like Bill Clinton and Christopher Walken [2] were more than a little impressive. For each turn, they generated a celebrity name and a Halloween-themed topic to talk about while imitating that celebrity. Jimmy, of course, had some awesome impressions up his sleeve too, channeling stars like Michael Caine and Dr. Phil. Check out Kevin's incredible celebrity impressions above, and then watch Christina Aguilera's spot-on Britney Spears impression [3] before enjoying even more must-see viral videos [4]!

Related:

• It's Hard to Pick a Favorite When It Comes to Benedict Cumberbatch's Celebrity Impressions [5]
• Hidden Talents: Watch Celebrities Do Impressions of Other Celebrities [6]
• All Right, All Right, All Rright: 7 Celebrities Doing Their Best Matthew McConaughey Impressions [7]
• You Really Have to Hear Adam Levine's Michael Jackson Impression [8]