Will Arnett is the odd man out in "Teenage Mutant Ninja Turtles."

On the TV show that remains, for many fans, the definitive version of the characters so far, Vernon Fenwick is an adversary, a foil both for April O'Neil and for the Turtles themselves. In this new film incarnation, Fenwick is the cameraman who works most often with April O'Neil (Megan Fox), and he knows that she wants out of puff-piece features. He also knows how the game works, though, and he doesn't really seem to believe she's going to get her break. He's the cynical voice of reality.

It's basically about as easy a paycheck as you can earn on one of these movies. "Teenage Mutant Ninja Turtles" hews closely to a formula, a blockbuster template that anyone should be able to follow at this point. You need an actor with killer comic timing to sort of hang out at the edge of the movie and make funny comments about what's happening. Jeff Goldblum in "Jurassic Park" is the all-time champion example of this, and it's little wonder he ended up the star of the sequel. He stole every scene he was in.

Arnett doesn't really steal this film, but it's a matter of the material, not him. He gives it whatever he can, but the film needed at least one more pass to make the punchlines really feel like punchlines. What he does well is keep an energy up that makes the film feel like it's urgent. I asked him about approaching that kind of technical acting and playing to the Turtles in scenes.

"I think that one of the things we had working to our advantage that a lot of other films like this don't is that we had the benefit for most of those scenes of actually having the actors who were playing those parts wearing mo-cap suits there on the set."

Arnett's a guy who entertains me because of the unexpected comic choices he makes, and I asked him if he's able to be free to try things in a film that is this technically demanding.

"I'm always pretty cognizant technically of where I'm supposed to be and what I'm supposed to be doing. It's important. It's one of the demands of the medium. The more you do, you have to be aware of where you are in relationship to the other actor, where you are in relationship to the camera, and etceteras etcetera…"

I mentioned to him how it feels like the list of skills required to be a movie star have changed from singing and tap-dancing and ballroom dancing and fencing to hanging off of buildings and reacting to tennis balls on sticks.

"Yes. We got to do some hanging on, some falling down… some running up. Some driving down. And, honestly, it's not something I was used to doing. I hadn't done a movie like this before, so this was something for me to learn.  And it was exciting to do. It's kind of like a different language."

"Teenage Mutant Ninja Turtles" opens in theaters this Friday.