Matt Damon Crashes Jimmy Kimmel’s Late-Night Monologue amid Years-Long ‘Feud’

Jimmy Kimmel and Matt Damon’s decades-long feud lives on. 

During the Oct. 3 episode of Jimmy Kimmel Live!, the comedian, 57, introduced special guest Frankie Focus, a neon green monster who has become the face of the cell phone ban in New York’s public schools.

“Jimmy, did you get a college degree?” the mascot asked Kimmel during his opening monologue. After Kimmel confirmed that he didn’t, Frankie said, “I could tell from watching your stupid monologue.”

Turning to the audience, the mascot quipped, “Isn’t he dumb?”

Before long, Kimmel realized that someone much more menacing was under the mask of the creature he deemed a “hot green sewer Labubu.” After a little scuffle, he pulled off the mascot’s head to reveal none other than the Jason Bourne star. 

“I made it on the show,” Damon, 54, shouted, after which Kimmel warned the audience, “Stop cheering for him. This is breaking and entering — again. You’ve done this before.”

As for why the Good Will Hunting actor forced his way onto Kimmel’s final show, taped from the Brooklyn Academy of Music’s Howard Gilman Opera House? Damon, who has been “feuding” with Kimmel since 2005, said he “just wanted to say goodbye.”

“I wore this costume because this is the last chance to get on the show,” Damon said, as melancholic music began to play in the background. “I know we’ve had our differences over the years, but I wanted to be here tonight for your last show ever.”

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Though Kimmel quickly clarified that the Oct. 3 episode wasn’t his last show, Damon went on to reference President Donald Trump‘s reaction to the late-night show returning to the air less than a week after it was pulled indefinitely.

“But the president canceled you, which I was a big fan of by the way,” he said. “When he said you had like zero ratings and no talent, I was like, ‘I’ve been saying that for years!’ ”

Kimmel first sparked his long-running feud with the Academy Award-winning actor two decades ago when he began his tradition of closing out episodes by saying, “Apologies to Matt Damon, but we ran out of time,” despite the actor having not been scheduled to appear on the show.

In 2006, Damon finally appeared on Jimmy Kimmel Live! for the first time as a guest — only to be suddenly cut off by the comedian at the end of the show. The actor then responded with a pre-planned flurry of curse words, and the following two decades were filled with couple’s counseling, subtle digs and many more of Damon’s attempts to sneak into Kimmel’s studio.

Despite their constant bickering, the two share a very special bond behind the cameras. In fact, Kimmel told Variety that he once saved the Martian star from nearly choking to death after being served pork ribs.

“I said, ‘We have got to get him to the hospital,’ because if he dies in my house, I’m going to prison for the rest of my life,” Kimmel recalled of the incident during the interview, published on Aug. 18. “I will never be able to explain this as anything other than a murder.”

He continued, “We did a lot of YouTube-ing and finally concluded that eating little bits of bread was the way to get that rib to work its way down into his stomach — and bread saved him. We tried the Heimlich many times. It was too far down.”