Ellen and Corey Streater couldn't have asked for a better birthday present -- an overnight camp-out at the zoo. But their dream gift becomes a nightmare when darkness falls. No one comes and they're locked in with the most dangerous animal of all -- an escaped criminal. He's stalking their every move, determined to kidnap them for ransom -- or worse! There's no time to waste. They're desperate to escape. They'll try anything -- even Ellen's crazy science project on animal communication. Can they talk to the animals and summon help before it's too late?