When Mr. Krabs gives SpongeBob the only key to the vault holding the Krabby Patty's secret recipe, SpongeBob and Patrick must keep it safe, until it is stolen by a passenger on their train.
After SpongeBob's pet Gary starts biting everyone, a rumor spreads through town that he has a rare snail disease, and as the Snail Bite panic builds, everyone's zombie-like behavior leads to a manhunt for Gary.
