Last week, the actor Devyn Dalton received, quite possibly, the world’s biggest compliment.

She was in New Zealand filming her next project, when she was awakened at 4 a.m. by the buzz of her phone. “I was like, ‘What is going on?’ It just blew up — my phone was going crazy,” Dalton, 34, said.

What was going on was that the actor Matt Damon, who plays Odysseus in Christopher Nolan’s interpretation of Homer’s epic tale, had said in an interview that she had “the greatest arms I have ever seen.” Her friends were sending her clips of the interview as it was ripping through the internet.

Damon had been discussing one of the film’s pivotal scenes when he gently corrected his interlocutor, who had mistakenly assumed the biceps in the shot were his own: They belonged to Dalton, who some might be surprised to learn is his stunt double. She’s a woman standing in for a male actor, for starters; she’s also 4-foot-6 to Damon’s roughly 5-foot-10 frame.

It’s a bit of movie magic, Damon explained. To film the battle against the man-eating Laestrygonians, Nolan used a technique called “forced perspective” to make Odysseus’ army appear minuscule.

A shot of Dalton from behind in the scene, holding a sword and ready to pounce at the giants, is used in one of the posters for the movie.