Spending the summer at her grandmother's house is the last thing Sarah wants to do. But her parents are staying there as they fix up the house after Grandma Winnie died. The tedious work turns into a thrilling mystery when Sarah discovers an unfinished letter her grandmother wrote: Strange things are happening behind the bookcase...

Alex Trumble is a pretty ordinary kid --- except for the fact that his IQ borders on genius, and he loves to read books on vortexes and time travel. But when two angry hit men kidnap his big brother, Alex’s life changes fast.

All Nate wants to do is find his parents, but when a unicorn falls ill, the young beastologist must put his job before his quest.