Ever since getting a little stepbrother named Harlan, Denver hasn’t felt like he fits into his own family. Lots of people find Harlan charming, but not Denver. His pesky stepbrother tags along everywhere Denver goes, breaking things and wanting Denver’s attention every. single. second. After an especially disastrous morning, Denver escapes to the forest, experiencing a whiff of ancient magic when he meets an old and dignified but lonely tree named Spiro. When Spiro offers to turn Harlan into a tree for a few hours, Denver jumps at the chance - only to realise he’s made a mistake when nobody, including his mom and stepdad, seems to remember Harlan existed. And now Spiro isn’t certain he can reverse the transformation. To save Harlan, Denver will need to find out what happened to Spiro to make him so disconnected from the other trees in the forest . . . but to do so the change he might have to make first is within himself.