Being too good looking has its downsides.

The author of the book of Emily Blunt's new movie "The Girl on a Train" thinks the actress is too pretty to play the lead role.

Paula Hawkins said although Blunt was made to look "a bit s--t," she was still too attractive.

"Oh, she's too beautiful to play [the lead role] Rachel," Hawkins told the Daily Mail.

Blunt plays Rachel Watson, an overweight divorcee with a bad drinking problem.

While Hawkins thinks Blunt's good looks are distracting, she added that she's a fan of Blunt's previous work in movies like "The Devil Wears Prada."