Jason is facing a boring summer. His parents have cut back on his TV time and actually expect him to read two books a week! But life gets very interesting when Jason presses a button on the TV remote control - and zaps a baby mastodon from the prehistoric era into his living room!

Now Jason has a giant-sized problem on his hands. Can his weird next-door neighbor help him send the creature back to his mother, or will Jason have a prehistoric pet for the rest of his life?