Eleven-year-old Jordie Marie Wallace has been waiting forever for someone to move in next door, so she is thrilled when Professor Reese arrives. Professor Reese has a laboratory in her basement and an extraordinary dog named Baxter who seems to understand everything Jordie says. Jordie and her younger brother, TJ, begin walking Baxter and helping Professor Reese in the lab. But being lab assistants ends up being more than Jordie and TJ bargained for.