Shonda Rhimes' 'Grey's Anatomy' To Make U.S. TV History With 332 Episodes

ABC’s “Grey’s Anatomy” is poised to become the longest-running primetime medical drama in U.S. television history this week, surpassing “ER ,” which previously held that title , The Hollywood Reporter reported. 

The medical drama, currently starring Ellen Pompeo, Jesse Williams and Justin Chambers, will air its record-breaking 332nd episode on Thursday. Shonda Rhimes, the show’s creator and executive producer, celebrated the milestone on Twitter Wednesday. 

“A lot has happened in 332 episodes and tomorrow we become the longest-running primetime medical drama,” she wrote. “People. You don’t want to miss this!”

“Grey’s,” which is currently in its 15th season, debuted in March 2005 with an episode titled “A Hard Day’s Night.”  Thursday’s episode, “We Didn’t Start the Fire,” will surpass the 331 episodes  of NBC’s “ER,” which ended its 15th and final season in 2009.

Pompeo, the actress-producer who plays Meredith Grey on the ABC drama, commemorated the show’s record-breaking episode in a post on Instagram touching on the “incredible” journey.

“We started this journey 15 years ago and this weeks episode makes history,” she wrote on Wednesday. “The truest thing about this journey is we appreciate how incredible it is.”

She continued: “We celebrate ALL of it. The ups and downs... the life lessons dance parties and the exhaustion of hard work..making history and being afforded the privilege of being able to. Thanks to everyone who has been on this ride with us... we are still having a ball.”