The tumbling curls Minnie displayed as she attended the film's photo call at the 54th BFI London Film Festival, had been neatly tucked away by the evening premiere to create the illusion of a chic, chin-length bob.
Celebrity short bobs are all the rage this season so perhaps Minnie is doing a trial run before going for the chop.
Do you prefer Minnie's hair long or short? Tell us your thoughts in the comment box below.
Fancy a temporary new 'do? Find out how to create a faux bob with our step-by-step guide.