The Girl On The Train
The cast, director and author of The Girl On The Train joined AOL Build for a live interview in London on 21 SeptemberTim P. Whitby / Getty

Emily Blunt and the cast of thriller drama The Girl On The Train have been doing the rounds, promoting the film alongside director Tate Taylor and author of the original novel. On Wednesday 21 September, they took part in a live interview in association with AOL's BUILD London series.

IBTimes UK were lucky enough to attend the event – here's a round-up of everything we learned about the eagerly-anticipated adaptation...

1. Taylor was adamant that Blunt had to play the film's lead

During the interview, Taylor revealed that as soon as one of his team presented the idea of Blunt playing protagonist Rachel Watson early on in the project, he was hellbent on securing her for the role. So much so, that two days after that seed was planted in his head, he was having lunch with her discussing the part.

2. Hawkins was inspired to write the source novel during her own commutes

"I used to commute a lot around London and I had one particular one – which is actually the District Line overground – it used to break down all the time. I would sit there, and there were these houses right by the track and I would stare into them and I was hoping that something interesting was going to happen. Nothing interesting ever happened! But I did start wondering what you would do, if you saw something that shocked you."

3. But now, she's writing a new book...

Hawkins didn't say much more on the subject other than the fact that she's currently working on another novel at the moment. She was reluctant to dish out any details but she did hint that it's likely to come out in the spring of 2017.

4. Blunt turned to documentaries to get inside the mind of an addict

In the film, Rachel is an alcoholic; something that Blunt felt was quite a challenge to play. "For me, it was a process of trying to really understand that state of mind," she told the audience. "It is a world I've never delved into. It is a world I've witnessed firsthand but I don't personally have that experience. So I watched a lot of documentaries for the emotional depth of what these people go through."

5. There are four main themes in the movie...

"Voyeurism, the illusion of domestic bliss, the pressures women face, the differences between what we need and what we want and finally addiction," are the threads at the forefront of the film, according to Blunt.

6. Luke Evans has footage of Blunt drunk... and it's going on the DVD Extras

"The Drunken Years" as moderator Edith Bowman put it... Okay, so he was joking, but wouldn't that have been brilliant? We wish he wasn't pulling our leg!

Haley Bennett in The Girl On TheTrain
Author Paula Hawkins thought that Haley Bennett was the 'perfect Megan' as soon as she saw her on setUniversal Pictures

7. Hawkins thought Haley Bennett was the "perfect" choice for Megan

"She's the perfect kind of beauty to play Megan," the author laughingly clarified after Bennett sarcastically responded "Thanks." From all we know about Megan, it wouldn't be the biggest compliment hearing you were like her personality-wise.

8. Lastly, the film is "shocking, dark and true to the book" confirms Hawkins

Diehard fans of the novel who are worried about the film tampering with it need not worry, Hawkins admitted during the live stream that the movie manages to be "true to the book" while also being "refreshing and different." She also went on to add that its "beautiful to look at and the performances will blow you away."

Also starring Orange Is The New Black's Laura Prepon, Justin Theroux and Rebecca Ferguson, The Girl On The Train is released in UK cinemas on 5 October. It will be shown on big screens in the US from the 7th.

Following on from the brand's continuing successful run in New York City, Build London is a live interview series which offers fans the chance to sit inches away from today's biggest names in entertainment, as well as technology, fashion and business.

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