Alec Karev will be surprised when his father (Dexter's James Remar) resurfaces after 20 years in the 200th episode of Grey's Anatomy, airing Thursday, and the family reunion will have an effect on his relationship with Jo.
"The last time Alex saw his father, he was abusing his mom, and Alex had beat the crap out of him," Justin Chambers told TVGuide.com of his character. "So this revisit is going to be very interesting to see what happens."
The official Twitter account for the show posted on Wednesday that Alex will reveal "an emotional secret" to his girlfriend in the Oct. 10 episode. Elaborating on where the couple will stand at the end of the episode, after Alex tries to deal with his father's presence, Chambers said their bond will only grow stronger.
"Alex has always been emotionally [backward], so whenever he starts to step out a little bit and feel secure, something happens and then he's pulled back in," he explained. "I think [his father's arrival is] going to make them strong, because she comes from a similar background - not the best childhood. They're going to be able to lean on each other, and she's going to help him hopefully get through it."
"She's someone who understands where he's coming from," he added. "She can call him on things, so it's going to make their relationship deeper."
The couple will also face obstacles once Alex's friends realize he is getting serious with Jo (Camilla Luddington).
"There's going to be some tension just because Jo's a little bit more outspoken," the actress told the website. "There's always that interesting relationship that happens with the women who are the friends in your life and then the girlfriend who comes in and tries to integrate into somebody's life. I think that will cause tension during this season."
Grey's Anatomy airs Thursdays on ABC at 9 p.m. ET. Thurday's episode is titled Puttin' on the Ritz. Watch a promo clip below.