It was just another day on the BMX street course for Billy Cruz. He lunged down the pipe, rode the ramp high into the air, and tweaked his bike for a perfect Superman -- when suddenly he lost his grip on the seat. Cruz hit the concrete -- hard -- and wound up in the hospital with several broken bones. Six long weeks later, Billy finally got back on his bike. But now, he can't help but hold back a bit on his tricks, and his scores are starting to suffer. To add insult to injury, Billy's best friend, Penny, has been acting strange since the accident.