Girl on the Train movie: How Emily Blunt, Justin Theroux entertained themselves on set

While The Girl on the Train is a nightmarishly dark film — possibly even darker than Paula Hawkins’ best-selling 2015 book — the atmosphere on set was surprisingly light. “I just feel I need to be really relaxed and happy if I’m to go there,” Emily Blunt says of her unhinged, alcoholic character Rachel Watson. “[Director] Tate [Taylor] was great at keeping the set very light and emboldening in that sense, that you felt you had a free rein to try anything. There actually was a lot of laughter on set.”

Much of that laughter, on Blunt’s part at least, was caused by her costar and friend Justin Theroux, who plays her ex-husband, Tom Watson, in the film. “He would make these hilarious videos, and he got me into doing it on set,” Blunt recalls. “It’s like he’s an acting coach, so he’ll send you acting tips and they’ll be ridiculous…. Justin’s are the absolute best. I’d be crying.”

Theroux cracked up remembering the videos, too. “Oh my god, that was my favorite thing to do, just to send terrible acting tips to her when she was at work,” he says. “She’s an old friend, so we had such a good time — like, a dangerously good time, to the point where we’re like, ‘We should probably just be a little more serious about this. But the material is so grim that we had to find time to laugh in between takes.”

Blunt adds that sometimes, she and Theroux would make their acting tip videos together, and send them in a group text to Theroux’s wife Jennifer Aniston, Blunt’s husband John Krasinski, and fellow actors like Will Arnett and Jason Bateman. “People were really lame about sending responses, I have to say,” Blunt jokes. “I think Justin and I were far more committed than anyone else.”

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