Ellen Pompeo and Katherine Heigl will reunite for the first time since the Firefly Lane star left Grey's Anatomy in 2010.
Variety pairs together actors to engage in intimate one-on-one conversations about their careers and lives twice a year.
Pompeo, 53, and Heigl, 43, will be part of the series' upcoming 18th season.
Last year, Pompeo came to her former co-star's defense in remarks on her Tell Me with Ellen Pompeo podcast.
In 2009, Heigl appeared on Late Night with David Letterman and said: 'I'm gonna keep saying this 'cause I hope it embarrasses them,' adding that her typical work day was 17 hours and that it was 'cruel and mean.'
Firefly Lane: Variety pairs together actors to engage in intimate one-on-one conversations about their careers and lives twice a year. Ellen, 53, and Katherine, 43, will be part of the series' upcoming 18th season
'I remember Heigl said something on a talk show about the insane hours we were working and she was 100% right,' Ellen said to her Grey's Anatomy friend co-star, Kate Walsh.
She continued: 'Had she said that today, she'd be a complete hero. But she's ahead of her time, made a statement about our crazy hours and of course, let's slam a woman and call her ungrateful.'
Pompeo — who exited the series last year — added that Heigl speaking out about their work hours was '100% honest' and was 'absolutely correct' about it all.
'And she was f***ing ballsy for saying it,' Pompeo said. 'And she was telling the truth. She wasn't lying.'
Heigl was blasted as being difficult to work with when she departed the long running medical drama.
She's maintained that she was simply misunderstood, telling the Washington Post: 'I may have said a couple of things you didn't like, but then that escalated to 'she's ungrateful,' then that escalated to 'she's difficult,' and that escalated to 'she's unprofessional.''
'What is your definition of difficult? Somebody with an opinion that you don't like? Now, I'm 42, and that s**t pisses me off,' she added.