LeBron James has endured his fair share of drama. When the basketball prodigy fled his native Cleveland Cavaliers and took his “talents to South Beach” to join the Miami Heat—an announcement made in a ridiculously orchestrated ESPN special dubbed “The Decision”—hometown fans burned his NBA jersey in the streets. And when he became the Yoko Ono of The Heatles, breaking up the “Big Three” to return home, Miami fans burned his jersey again, before realizing they lived by a beach and should stop whining.

And so, after spending close to 12 seasons trapped in a seemingly endless NBA soap opera, James has decided to take his considerable “talents” to Hollywood. Tinseltown had been courting King James for quite some time, and rumors surfaced early last year that Warner Bros. was developing a sequel to the Michael Jordan-starrer Space Jam as a star vehicle for the other No. 23. While that project doesn’t seem like it will come to fruition, the 30-year-old decided to opt for a far less predictable avenue for his big acting debut: Judd Apatow’s Trainwreck.

Trainwreck, which had its world premiere Sunday night at SXSW, centers on Amy (Amy Schumer), a reckless thirtysomething who’s taken her disturbed father’s advice and sworn off monogamy—instead opting for a revolving door of empty, booze-fueled one-night stands. When she’s sent by her mean editrix (Tilda Swinton, fabulous) to profile a rising sports doctor (Bill Hader, utterly charming), her vow is seriously put to the test.

Now, make no mistake about it—this is Schumer’s movie. The stand-up comedienne proves adept at both comedy and drama in what will surely prove to be a gigantic launch pad for her acting career in the same way Bridesmaids’shot Kristen Wiig to the A-list.

But Apatow’s film is also a showcase for James, who steals every damn scene he’s in. And this is not the cameo many thought it would be, but a substantial supporting role in the film as the lifelong best friend to Hader’s doctor. We’re first introduced to James—playing himself—when he pops into Hader’s office while Amy is interviewing him. He’s left his sunglasses on the couch, and drove 40 minutes back to his office to retrieve them because he says he’s “not spending another thirty dollars to buy a new pair at Sunglass Hut.” Then, he gets serious. “Are we watching Downton Abbey later?” he asks Hader. “Listen, I’m watching it tonight because I’m not gonna go to practice tomorrow and all the guys are talking about it, and I’m left out.”

The crowd cracked up at the basketball stud’s deft comedic timing. His next scene, he goads Hader into calling Amy the day after they first have sex, cheering his pal on from the sidelines and loudly proclaiming to the entire restaurant, “My boy got intimate… SEXUAL INTERCOURSE! Oooooo!” Later, he complains about why Hader never visits him in Cleveland when he visited him all the time in Miami, and then demands that they split the check evenly because they’re “equals forever.” Hader slaps down his plastic, and James realizes he’s left his wallet in the car, cementing his cheapskate status. More laughs.

But James’s best scene—and one of the funniest moments in the film—occurs during a basketball demonstration that Hader takes sports-hating Amy to. The relationship is new, and when Hader goes off to help an injured cheerleader, James sits in his seat—and then proceeds to grill Amy about her feelings towards Hader. “When you look up in the clouds, do you see his face?” he deadpans. “When you hear his voice, does it remind you of a song?” Then, he warns her to not hurt his BFF. She chuckles, thinking this hulking athlete is kidding, but he stares her dead in the eye, completely stone-faced, for a good five seconds. It’s hilarious.

After his winning turn in Trainwreck, that Space Jam 2 flick doesn’t sound so terrible after all.