Lava Grey is an inquisitive talking cat on Hawaii's Big Island. She gets her name from the abundant rocks and boulders on the island. For nine years, she has lived on a three-acre plot with her caretakers, Auntie Melsy and Major Tom, but she has decided she needs to see more of the Big Island beyond her home.

She and Major Tom set off on an adventure in a1981 Mercury Lynx, an old electric-powered car. Together, they venture away from their home. Along the way, Lava Grey deals with dog and cat hitchhikers, samples local pastries, and even meets an army of rats.

Adventures can sometimes be dangerous, as Lava Grey soon learns. She must come to terms with her fear of dogs and realize that opposing sides can come together with a common goal. Lava Grey has always been book smart, but she quickly becomes life smart with the help of Major Tom and their unique electric vehicle.