hasn’t let his star power go to his head.
dished on what is was like starring alongside Affleck in the upcoming film
, admitting that she was pleasantly surprised by how grounded the actor was on set.
“He’s very smart and very funny and is definitely a practical actor,” Kendrick tells PEOPLE in this week’s issue. “He comes to work to get his job done and to make the best movie possible but is still really normal-sauce off-camera.”
In the film, Kendrick, 31, plays a clerk who befriends Affleck, a socially-awkward accountant who keeps the books for some of the world’s top criminals.
For much more on The Accountant and other fall movies, pick up this week’s issue of PEOPLE, on newsstands Friday.
“The idea of the world’s sexiest, most dangerous accountant is certainly the kind of delicious dichotomy that makes for a great movie,” says Kendrick. “The plot is definitely like a puzzle. I was there when we filmed it and still, the second time I watched the movie I was like ‘Oh, it’s even better the second time.’ “
But just because Kendrick may play a character entrenched in the world of numbers doesn’t mean she’s a natural born math whiz.
“Oh my god no, it’s so embarrassing,” she jokes. “My mom is an accountant, so I gave her the script and was like, ‘Can you please help me understand what is happening in this movie?’ I basically managed to retain as much information as she gave to me for the duration of the filming and the second we were done it was like my brain dropped this proverbial 50 pound bag I’d been carrying around. And it was like ‘I’m never picking that up again.’ “
hits theaters Oct. 14.