As Deborah Vance’s second chance at hosting her own late-night show starts to become a reality on season 4 of Hacks, she’s running into a friendly face — and a pissed-off one.

Entertainment Weekly has the exclusive first look at comedy legend Carol Burnett and late-night’s Jimmy Kimmel, who both guest-star on the Emmy-winning Max comedy. Burnett will appear in the show’s fourth episode, offering some critical advice to Jean Smart‘s Deborah who’s overcome by a sudden bout of anxiety, while Kimmel pops up in episode 5, hunting down Deborah to give her a stern warning about a guest she’s trying to poach for her new show.

“He brought some of his own dialogue that was really good,” series co-creator and costar Paul W. Downs reveals to EW of jokes referencing some other last-night hosts both past and present. “He went there.”

Jimmy Kimmel confronts Jean Smart’s Deborah Vance on ‘Hacks’ season 4. Jake Giles Netter

Burnett doesn’t offer any burns, though — rather, during a chance encounter, the comedy trailblazer shares some solicited advice with Deborah after she has a panic attack during a rehearsal for the debut of Late Night With Deborah Vance.

“It was such a treat to have her,” Smart says of Burnett, who played her mom when they both guest-starred as Wendie Malick’s family on a 2013 episode of Hot in Cleveland. “There’s nobody like her in terms of comedy and just being an incredibly cool human being…. If I can be like her or Betty White when I’m in my 90s, I’ll be a very, very happy lady.”

The casting offers a rare moment of vulnerability for Deborah, who’s “having stage fright for the first time in [her] life,” as Smart explains — and there’s perhaps no one better suited for the cameo. “She wouldn’t admit that to anybody except somebody like Carol Burnett.”

Burnett says she was “thrilled to ‘get in the sandbox'” with Smart — and support Deborah on her new adventure. “Isn’t it great that age doesn’t matter when you watch someone as wonderful as she is? Way to go, Deborah!”

Carol Burnett appears as herself on ‘Hacks’ season 4, when she runs into Jean Smart’s Deborah Vance in a doctor’s office. Kenny Laubbacher

In addition to Burnett and Kimmel, Julianne Nicholson, Michaela Watkins, and Eric Balfour will also guest-star on Hacks season 4. Helen Hunt, Tony Goldwyn, Kaitlin Olson, Jane Adams, Lauren Weedman, Christopher McDonald, and Poppy Liu will also reprise their roles.

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The first two episodes of Hacks season 4 premiere Thursday, April 10 on Max at 9 p.m. ET.