New The Girl on the Train trailer: Emily Blunt isn't 'helping anybody' 

7 things we loved about the 'Girl on the Train' trailer

The first trailer for 'The Girl on the Train' debuts

barreled into the station Monday, giving viewers a closer look at Emily Blunt’s depressed alcoholic Rachel Watson.

Based on Paula Hawkins’ best-selling 2015 thriller,

follows Rachel as she invents a fantasy life for a couple she spies from the train on her morning commute – then grows dangerously involved in the police investigation when the wife (Haley Bennett) turns up missing. But to hear Rachel tell it, her motivation was purely innocent: “I used to watch this perfect couple,” she says in the new trailer. “They were the embodiment of true love.”

As Rachel gets tangled up in the case, other questionable details present themselves: Like how Megan (Bennett) and Scott (Luke Evans) live a couple of houses down from Rachel’s ex-husband, Tom (Justin Theroux) and his new wife, Anna (Rebecca Ferguson). Naturally, suspicions eventually turn to Rachel herself:

“Because, I’m helping find Megan,” Rachel says.

“I don’t think you’re helping anybody,” he tells her.

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