'Arrow's' Colin Donnell: 'You're Going to See a Harder Edge From Tommy'

The actor talks with THR about how his character will handle news of Oliver's secret and balance news that his best friend is a killer.
The CW
"Arrow's" Colin Donnell

To say Arrow's Tommy Merlyn has a lot on his plate right now would be an understatement.

After learning that his best friend Oliver (Stephen Amell) is the hooded vigilante cleaning up Starling City, his girlfriend's mother returns with news that her late sister might still be alive. Then there's the small detail that the upstanding guy still has to learn: that his father Malcolm (John Barrowman) is the Dark Archer -- who is heading for a confrontation with his hooded best friend.

The Hollywood Reporter caught up with Colin Donnell to preview what's ahead on the CW's DC Comics adaptation and what's ahead for Tommy.

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The Hollywood Reporter: How will we see Tommy grapple with Oliver's secret identity?
Colin Donnell: It's going to be interesting. That revelation throws everything into turmoil and all the relationships start shifting -- especially the one between Tommy and Oliver. The impact doesn't end there; because of the closeness between Oliver, Tommy and Laurel, it's going to seep into the relationship between Tommy and Laurel and the relationship between Malcolm and Tommy shifts, too. You might see the two of them being pushed closer together.  

THR: Tommy now knows that his dad can hold his own in a fight -- as we've seen -- and his best friend has a secret identity as a killing vigilante. How will this impact how he feels about the people he thinks he knows? Might he have some trust issues?
Donnell: Most certainly! (Laughs.) Tommy is one of the only people who really reacts to finding out his best friend is a killer in a way that any of us might: Great, you're cleaning up crime, but you're also killing a lot of people in the process and he doesn't like it. For Tommy, it's not just the issue of somebody lying to him that is a problem -- it's what he's lying about, as well. Tommy has some stuff to figure out (laughs).

THR: Will Tommy keep Oliver's secret from Laurel (Katie Cassidy), or will he use that against him?
Donnell: The burden of trying to keep this secret in is a lot to bottle up. That's one of the things that will ultimately impact Tommy's relationship with Laurel. I don't know if he'd ever tell her outright because that'd be a lot for anybody to handle. Tommy is a person of his word and the fact is he's going to make a promise to Oliver not to tell. I don't know if there is anything that could really force him to play that card.

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THR: Might Tommy warn his father about having the vigilante on speed dial?
Donnell: That's a good question and I'm going to leave it at that! (Laughs.)

THR: What kind of role will Tommy play when Oliver and the Dark Archer go head-to-head?
Donnell: Your guess is as good as mine. If Tommy were to ever find out who his father really is, you have your father and best friend -- who has been your brother -- and they're two people you barely know who they really were. Who knows what side of the line Tommy might fall on.

THR: How soon might we see Tommy begin to devolve from the nice, stand-up guy we've seen so far?
Donnell: Soon! (Laughs.) You're going to see a harder edge from Tommy, not necessarily with darker thoughts but he's going to have a really hard time with everything and he doesn't take it in a woe-is-me way -- he really pushes back. It's a bit of learning about Oliver and in episode 19, The Count comes back and Vertigo makes an appearance again -- and Tommy becomes a suspect in that. He's going to have a real issue with the people who not only accuse him of that but also who don't immediately stand up for him. 

THR: Dinah Lance returns to tell Laurel that her late sister, Sarah, might still be alive. How will Tommy support Laurel during this?
Donnell: You see Tommy trying to be the best boyfriend he can and be supportive. He's very distracted lately and he's not necessarily as there for Laurel in the way she needs him to be. It's going to be sad.

Arrow airs Wednesdays at 8 p.m. on the CW. Hit the comments with your thoughts on Tommy's potentially dark future.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit