The Rewind Protocol (Shadow World Paradox, #5)

14-year-old Jax finds an old pager that allows him to "rewind" time by exactly 60 seconds, once per day. It seems like the ultimate social cheat code until he realizes that every time he rewinds, a "Shadow Double" of himself is created in a parallel timeline. These doubles are starting to slip into his world, trying to take over his life. Jax has to find the other "Protocol" users at his school to figure out how to merge the timelines before he is replaced entirely.