Emily Blunt is the one thing stopping The Girl On The Train from going off the rails, according to critics of the best-selling thriller's film adaptation.
The big-screen version of Paula Hawkins' novel opens in cinemas on Wednesday, but reviewers have panned its thin, holed plot and praised Emily as its saving grace.
The action has moved from London to New York and she plays alcoholic main character Rachel Watson, who is struggling to move on from her broken marriage.
During her daily commute into Manhattan, she obsesses over a couple whose home the train passes, which turns out to be a few doors down from her ex and his new wife - but the plot thickens when the woman from the pair she has been watching goes missing.
The Guardian's film reviewer, Peter Bradshaw, said Emily had done her best in tough circumstances.
He wrote: "Emily Blunt does her considerable best with this exasperating and plaintive role. In movies from The Devil Wears Prada to Sicario, she has shown that she can look good while being ill or messed up: strong, believable, human, vulnerable. But this part doesn't give her any scope for recovery, for the all-important mastery and survival: she just always looks under the weather ... Fans of Paula Hawkins's thriller might find themselves sticking to the book."
The Daily Telegraph's Tim Robey agreed that the star was the best thing about the adaptation: "Rachel is played - thank goodness - by Emily Blunt, who throws every stray ounce of feeling and insight she can at the role."
He went on: "It's as if the book has been given a full-body massage en route to the screen, teasing away some of the spinal kinks that actually made it interesting."
Robey concluded: "Blunt's Rachel might be a soused and broken bit of human wreckage, but she's better than all this: there are too many moments when you wish this raddled stalker had simply been allowed to direct her own film."
The Radio Times's critic, Stella Papamichael, weighed in with: "Director Tate Taylor (The Help) has created a very neat (if rather too tidy) domestic thriller, but he hasn't exploited the medium to bring anything fresh to the story, riding instead on the solid track the book provides."
She added: "A few small holes in the plot don't break the spell, but they are more obvious on film where a novel can bridge those gaps with other deeper, psychological insights."
In the Irish Times, Donald Clarke said there was a fundamental problem with the script.
He wrote: "As is too often the case these days, somebody needed to tear the source material to shreds before embarking on the adaptation."
The Girl On The Train is released in cinemas on October 5.