What does 'let it bleed' mean in the following sentence?
Though the actors give their all, notably Stellan Skarsgård as the brother of the missing Harriet and Joely Richardson as an estranged relative, the film hangs back when you want it to come out swinging. Only Mara lets it bleed. Her defensive, bruised-animal performance inexorably draws you in.
Is it common enough in daily conversation or English texts? I have seen it before, but it also in a film review (and The Rolling Stones album). Could you give me another example of its use in a sentence? If possible, the origin of the phrase would be nice too.