Nick borrows David's toy dinosaur for a week and promises he won't lose it. When Nick loses it the very next day, he has so much fun hunting for the tiny dino that he "loses" it again...and again...and again...The dinosaur spends a fun-filled week doing things like guarding a sand castle, dangling from a shopping cart and stalking fossils at the science museum. When practical joker Nick returns the toy, David asks to borrow Nick's new firetruck----he promises he won't lose it.I'm not sure why there needs to be a friend involved. The losing something and the adventures of the lost toy sound interesting by themselves. I'd have a look.