Rewind Watchers Series, Book 2.

A mysterious camera gives Adam the chance to change the past In the dead of a Vermont winter, Adam, Edgar, and Lianna skate onto the pond to practice hockey. Suddenly, a crack in the ice sends the two boys tumbling into the frozen water. When he wakes up, Adam remembers nothing-and his best friend is dead. Four years later, guilt haunts Adam. He and his friends are playing laser tag near the pond when he stumbles over a backpack. Inside is a vide...