Kenan Thompson to guest judge 'America's Got Talent'

"Saturday Night Live" legend Kenan Thompson is set to guest judge "America's Got Talent" on Tuesday.

In a full-circle moment, Kenan Thompson is returning to NBC’s America’s Got Talent as guest judge for the Quarterfinals 3 episode on Sept. 1. He will be filling in for judge Simon Cowell, also AGT‘s creator/executive producer, who has been sidelined by back surgery. Cowell was not on the show this week as he is…