Allison Janney 'arrested' Emily Blunt 'for jouer la comédie infractions' on The Girl on the Train set 

This Week's Cover: Emily Blunt stars in the complex 'Girl on the Train'

How Emily Blunt, Justin Theroux had fun on 'The Girl on the Train' set

From filming goofy videos in their downtime to bonding with costars, the

Girl on the Train cast, by all accounts, had a great time on set despite the film’s heavy plot. But Allison Janney, who plays Detective Riley, might have had the best time: She 

enjoyed stepping into a very different role for the first time.

“I’ve never played a detective before,” Janney tells EW. “I felt a little out of my element — I usually play crazy ladies.” With Emily Blunt playing unhinged alcoholic Rachel Watson and Haley Bennett as mysterious seductress Megan Hipwell, Janney’s “straightforward detective” grounded the cast in a way. But that doesn’t mean Janney had to take her character seriously the

time: “I felt pretty powerful with the costume on… it made me walk differently,” she says. “It was fun to walk around with a badge and a gun, going around making citizen arrests, ‘actor arrests,’ on set and being silly.”

“I arrested Emily a number of times for acting infractions,” Janney remembers, laughing. “ ‘You were acting better than I was in that scene. I’m going to have to take you down to the station.’ It was very fun.”

Director Tate Taylor, Janney’s longtime friend, actually rearranged the film’s two police roles to give Janney the part, making the female detective a more prominent character than the male. “In the book, it’s a male detective with a female sidekick who doesn’t [really] talk,” Taylor says. “So I made it one detective, and made it all Allison.” Since 

peers into the lives of three women — Blunt’s Rachel, Bennett’s Megan, and Rebecca Ferguson’s Anna Watson — Taylor found it fitting to add one more prominent female character into the mix. Here’s hoping Janney gets another chance to flash a badge in the near future.

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