The film starts with a super:

"NSB Presents. The buttocks Thomas got from standing on the train everyday for a year." We then see a man walking on the beach dressed in bathing-shorts. Behind him people are fainting because he has such a nice butt - it's too much to handle. Cut to the train where the same man is standing, while he is secretly training his butt-muscles. The last super reads: Get a nice butt. Travel by train.