Thomas's class is taking a weekend nature trip to Devil's Island, and his bionic best friend is coming along for the fun. But danger is in the air. Legend has it there's a secret volcano on the island. Could someone be plotting to activate it and destroy Thomas's nearby hometown.
Thomas Wiggins' sweet new dog McGrowl is changed forever by the creepy Dr. Minderbinder, who transforms McGrowl into a dog with superpowers, and now Thomas and his pal must find a way to thwart the veterinarian's evil plot.
It's up to Thomas and McGrowl to use their powers of telepathy and bionic-doggie strengths to sniff out the truth about a suspicious mayoral candidate who has his eye on the quiet town of Cedar Springs.
