Before Council of Dads, Michael O'Neill was the shooter on Grey's Anatomy

If you’re wondering where you’ve seen Michael O’Neill from Council of Dads (premiering tonight at 10 p.m. on NBC), ask a fan of ABC’s Grey’s Anatomy. In the two-part season 6 finale, O’Neill played a bereaved husband named Gary who shot Derek (Patrick Dempsey) and Alex (Justin Chambers) and killed interns Reed (Nora Zehetner) and Charles (Robert Baker). Rather than shoot his other target, Webber (James Pickens Jr.)— who he also blamed for killing his wife at Seattle Grace — Gary turned the gun on himself.

“Somebody told me the other day that over 16 million people saw that episode,” says O’Neill, who adds that he underwent therapy after the role. “On the one hand, it’s gratifying to be a part of something that was so impactful.... [And] I’m awfully grateful that I’m getting to do what I’m doing now.”

In Council of Dads, O'Neill plays Larry Mills, a friend who helps out Robin Perry (Sarah Wayne Callies) after tragedy strikes her brood. It's been a long time since O'Neill played the shooter during Grey's sixth season but people still bring up the role to the actor.

"I had a producer ask me not long ago if I would do the same role now and I said, no," said O'Neill. "I don't think I can do it now. I'm older. Life looks different to me now. My kids are pretty much grown. I'm trying to keep a roof over their heads. But it was compelling television and I'm so grateful Shonda [Rhimes] trusted me with it."

The shooter episode of Grey's Anatomy can be found on Netflix.

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