The 'Saturday Night Live' star sat in for the longtime judge on Tuesday.
'AGT' returned with live shows from Universal Studios Hollywood. See who made it onto the next round.
The 'AGT' judge broke his back in an electric bike accident earlier this month.
'AGT' returned on Tuesday with live shows from Universal Studios Hollywood.
ET has learned that the 60-year-old 'America's Got Talent' judge is walking again as part of his recuperation.
Cowell went through six hours of surgery after breaking his back on Saturday.
'AGT' season 15's live quarterfinals are around the corner, and here's a look at who will be facing off first!
'America's Got Talent' returned Tuesday for season 15's judge cuts, and one act left the judges in awe.
Liz Lemon got the gang back together for a one-night return to TV.
The comedian opened up to ET about his roller coaster journey from the 'AGT' stage to the hospital and how he made it through.
Poet Brandon Leake brought the judges to tears with his incredible performance on Tuesday's new episode.
The stand-up comic faced the unique challenge of doing stand-up to an almost empty theater in this look at next week's new episode.
The sitcom star said he was 'so pumped' to be a judge as he filled in for a sick Heidi Klum.
Cowell gave the ultimate honor to the WAFFLE Crew dancers on Tuesday's new 'AGT.'
