George had filmed a pilot with Grey's creator Shonda Rhimes and then went on to star on her production company's short-lived ABC drama Off the Map. So the actor was a well-established member of the Shondaland family when he booked the role of Ben.
"I think they originally envisioned Ben showing up for three or four episodes," George tells PEOPLE of joining the medical drama in 2010 as one of the doctors who joined the staff when Seattle Grace merged with Mercy West. "But I guess Shonda just decided to not get rid of him."
Mitch Haaseth / ABC
"One of the great things about working with an amazing ensemble cast like ours is that the focus rotates," he says. "As a man with a family, I appreciate not being in every scene every day. But sometimes it's great to get to run up and grab the rock. I said, 'It's time to put on my big boy acting pants and get this done!' "
Since joining the cast in season 6, George has watched his character dominate his field as a top anesthesiologist, fall in love with – and marry – Dr. Miranda Bailey (Chandra Wilson), go back to medical school to become a surgeon and return to Grey Sloane Memorial as an intern.
"Ben spent years at the top of his field but now he's had to be humble because he's still learning to be a surgeon," says George.
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That battle between ego and humility has caused conflict for Ben in recent episodes.
Ben's working and marital relationship with Miranda was strained after he chose to cut a man open with a clipboard rather than waiting to transport the critical patient to an operating room.
"Ben had to make a judgement call," George explains of that situation. "And Miranda was left questioning his judgement."
Though George can not discuss the details of Thursday's episode, the actor does reveal that it puts Ben in another precarious situation that could further strain both his professional and private life.
"Ben is put in a position where he has to make a hard call," George teases. "It's the worst possible scenario for any surgeon to find themselves in."
But whatever the details of the episode, George praises Grey's writers for continuing to find new stories after all these years.
"These writers are out to prove they are not sleeping on the job in season 12," he says. "And they never present a story with a cut-and-dry answers. Like real life, nothing is ever black and white on this show. It's always – dare I say it – shades of grey. Did I really just say that?!"