Photo: Maarten de Boer/getty

Peter Gallagher

Grey’s Anatomywill have a new doctor in the house when it returns for its 18th season next month.

Peter Gallagheris joining the cast, PEOPLE can confirm, playing Dr. Alan Hamilton — a medical professional with ties to the title heroine’s mom, Dr. Ellis Grey (Kate Burton).

Deadlinewas first to report the news.

The actor, who turned 66 on Thursday, will appear in the season premiere ofGrey’s, slated for Sept. 30, where he’ll meet Meredith (Ellen Pompeo).

Gallagher’s character just might be the key to Burton’s return to the series,which was announced earlier this month.Dr. Ellis Grey famously died back in season 3 after suffering from Alzheimer’s, but later appeared to Meredith in a dream during season 15, which aired in 2019.

Burton is slated to reprise her role in multiple episodes, including the season 18 kickoff.

Ellen Pompeo as Meredith Grey onGrey’s Anatomy.Kelsey McNeal/ABC

ELLEN POMPEO

Gallagher has been working in Hollywood for more than four decades now, with memorable roles on stage (like 2015’sOn the Twentieth Century, opposite Kristin Chenoweth) and screen (American Beauty,Palm Springs, andBurlesque, to name a few).

He’s best known to television fans for playing Sandy Cohen onThe O.C., and has also recurred onLaw & Order: Special Victims Unit,Californication,Covert Affairs,The Gifted,Zoey’s Extraordinary Playlist, andGrace and Frankieover the years.

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Pompeo has starred as the titular doctor inGrey’s Anatomyfor the entirety of its 17-season run, but hasexpressed uncertainty about her future with the showin recent years. “This yearcould be it,” she toldVarietyin October, ahead of the season 17 finale. The showwas renewed for season 18in May.

As for acting roles afterGrey’s (whenever that is), the Golden Globe nominee admitted this month that she’d be fine hanging up her acting hat when the long-running ABC series takes its final bow.

“I’m not saying I’ll never act again, I very well may, but I’mnot super excited about continuing my acting career,” she said on theLadies First with Laura Brownpodcast.

“The acting, even though I haven’t done a million different roles, I feel like I’ve done it,” Pompeo added. “Sitting around in trailers, traveling around, shooting this in Atlanta, shooting that in Vancouver. I have no desire to go sit in trailers at 11 o’clock at night and wait to shoot scenes and have ADs knock on my door and tell me when I can eat lunch. You know, it’s for the young at heart. It’s for the youth!”

source: people.com