Jackson and Quigley were this close to joining the FBI (Frosty Bureau of Investigation), until Jackson’s mom found out and they ended up scrubbing seagull poop instead. At least they have Uncle Bryn’s birthday party to look forward to. But when they get to the ice cream parlor, the FBI agents are acting strange. Instead of talking, Uncle Bryn and his friends just finish their glowing green ice cream, then jump into a waiting ice cream truck and disappear.

It’s obvious that something has gone very, very wrong, and now Uncle Bryn is suspected of being a master thief! Can Jackson and Quigley solve the case before Uncle Bryn is locked away forever?