Trevor's mum has offered him £30 to walk the dog every day of the holidays. But Streaker is no ordinary dog, she's a rocket on four legs with a woof attached. Trevor's sure there must be a way to control her and Tina, his best friend, knows about training dogs. Their attempts involving such things as a pair of roller skates, a mobile phone and a bicycle, always lead to trouble. Horrid Charlie Smugg bets Trevor he can't train Streaker before the end of the holidays. But Trevor and Tina construct a dream plan and Charlie has to eat his words.