Whishaw is always great. SPOILER ALERT!
Repressed, unhappy, broke, miserable. Boring, repetitive, but curiously demanding job (what of the guy who "recognises" him?), something has to give. After a birthday from hell at his parents' house, he finally lets off steam: robbing banks, running wild, creating mayhem - the one good thing he does is stop an appalling Best Man un mid flow.
Despite (surprisingly light) injuries following a nasty tumble off a quad bike, then a fight with a motorist, he ends up happy. Jolly good.