Credit: ABC

Alex (Justin Chambersfinally rips the bandage off his long-festering resentment of his deadbeat father in Grey's Anatomy Season 10, Episode 12 — "Get Up, Stand Up," which airs tonight, December 12, at 9 p.m.

Check out the sneak peek below for proof.

"I got a question for you," Alex starts as he comes into Jimmy's room. "I recognized you the first time I saw you. How do you forget a wife and three kids?"

The answer? Drugs, Jimmy says. "I remember you, though. I remember you used to laugh in your sleep … You were just a happy kid," he says, sadly. "I guess I fixed that, huh?"

Alex recounts a happy memory of Jimmy taking him to a crappy fair and riding all the rickety rides, and Jimmy tells him that Alex's mother had a breakdown that day, suffering from paranoid delusions. He even calls the woman "bug-eyed crazy."

"Mom was not the problem," snaps Alex. Jimmy starts saying that it was a "strain" to be with her, but that really sets Alex off, considering Alex surely felt the strain even more than his pops did.

"Who do you think took care of her? Kept track of her? Got her committed so that she wouldn't hurt herself? Who do you think took care of your kids?" Alex yells, getting more and more infuriated by the second. "If that's your best, then you should just hang it up. Your best is worthless. I was the dad! I was a kid, but I was the dad! You were nothing! You were gone! You're worthless!"

It sounds a little soapy in writing, but Justin really sells it. In fact, the scene could be some of his best acting yet. Check it out in the video below.

Grey's Anatomy Season 10, Episode 12 — "Get Up, Stand Up" — airs tonight, December 12, at 9 p.m. ET on ABC.


Dan Clarendon is an assistant editor at Wetpaint Entertainment. Follow him on Twitter and Google+!