Summary Eight months in, and 13 Cubes remain. They have made great progress, but Peter still wonders if any will actually be ready to fight in just four months. Boyd is in constant pain but after more than a year since getting the program going he is not walking away. Rick is hurting badly, too: Peter gives he and Boyd each a week off to rest. The fun of the early days is gone - training is nothing but grind now. Peter takes the Cubes to the beach for a change of scenery from the gym. The Cubes go on a rafting field trip, too, for some time together away from the gym. Jock wants to see the year through but the arrival of his first child changes his outlook. Two other Cubes drop out. Ten weeks from fight time, and 10 Cubes remain. They go for their professional licenses. Boyd worries he won't pass, that all the training was for nothing. Robin Black, a 40-something fighter, is to be Boyd's first pro opponent. Peter ups the training ante again, taking the Cubes to the legendary Renzo Gracie Academy in New York City. Two months till fight night.

• Documentary