Chris O'Donnell, The Company
Despite having more than a dozen films under his belt at the time — from the serene (Circle of Friends) to the bombastic (Batman Forever) — the gig that Chris O'Donnell credits with putting him in The Company, TNT's three-week, six-hour miniseries about the early CIA (premiering Sunday at 8 pm/ET), was his turn as a dreamy (though not McDreamy) veterinarian on Grey's Anatomy.

"I had a fantastic time doing it, and I think I got a good 'pop' off it," O'Donnell says, fondly recalling his run as Meredith's onetime paramour, Finn. "I've known [executive producer] Ridley [Scott], and we've talked in the past about working together. When they were putting this together, those Grey's episodes were on and they thought, 'Let's get Chris.' The timing really worked out for me." O'Donnell, though, is at a loss to detail what exactly it was about Finn that Scott took a shine to: "I delivered a horse...?"

Now, as The Company's Jack McAuliffe, O'Donnell delivers a gripping tale of Cold War CIA agents fighting a ruthless Soviet enemy. Posing as a Yale alum with "a soft job in the State Department" and stationed in Berlin, McAuliffe reports to Alfred Molina's Harvey Torriti (aka the Sorcerer) and puts life and love at risk to ferret out a mole (or two) within their own ranks, at times bumping up against counterintelligence agent James Jesus Angleton (aka Mother, played by Michael Keaton). There are codes to be cracked, informants to be vetted and shadows to be dodged on dank German streets: It's a grown-up version of the spy-vs.-spy game we all played in our youth. "When I was a kid, I was totally into that," O'Donnell shares. "You get that first set of walkie-talkies and you tape it so [the channel is] open and you plant it in a room and listen in.... That was always exciting."

But in TNT's sprawling saga, the stakes are high, and more real. "Much like Jack goes from being really eager to serve his country and not realizing the realities of it, this project opened my eyes a bit," says his portrayer. "It seems like a glamorous job when you go see a James Bond film, but if you really start to think about these guys living in these countries, not really able to talk to anybody about what they're really doing, and the danger they put themselves in... it's not like you're in a war with other troops and you're fighting together. These guys were out there so naked and exposed."

Based on Robert Littell's historical novel of the same name, TNT's The Company had to take some liberties with its source material, a compromise O'Donnell is familiar with. "When we did Circle of Friends and I read Maeve Binchy's original book, I thought, 'There's so much good stuff we're leaving out!'" the actor recalls. "It's hard, the choice you make about what to keep and not keep. [Littell's The Company] has so many great stories, but you can't keep everything, and I thought they did a really good job. You get a real sense of what it must be like for these guys. There's action, emotion, deception.... The technology has really changed today, but the lengths they went to, using dollar bills and [encrypted] radio messages [to relay information], was amazing."

And a far cry from tending to Meredith Grey's pooch, a responsibility O'Donnell may have held onto longer had TNT not come calling. "I forget how many [Grey's Anatomy] episodes I originally signed on for, and then they asked me to stay longer, which I did. But then [The Company] came up, and I said to [Grey's creator] Shonda [Rhimes], 'I really want to do this [miniseries], but I don't want to screw you guys up. Let's try to do both for a while here.' But I kind of knew.... " After all, as O'Donnell adds with a laugh, "Finn's a vet! It's not like they're opening a wing of Seattle Grace serving animals."

In any case, would O'Donnell return to complicate Mer's love life yet again? "I had a good time and I don't know how the story would be, but it would be fun, I suppose," he says. "But I have no plans to."

Next Friday in Interviews & Features: Our one-on-one Q&A with The Company's Alfred Molina.

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