December 31st: party time! And Leo's parents are throwing a costume party. Finger food, music, dancing and fun, is more than one needs to attract Mot. Turning up unexpectedly, the monster mingles with the guests who consider his costume to be a great success. One small problem: Mot can't hold his champagne! One tiny sip is enough to send the monster into a strange torpor punctuated by violent hiccups which transport the house through the centuries. New guests gush from every epoch: an enterprising Bedouin, a stunned medieval samurai, an annoyed gorilla, etc. The only one not enjoying himself is Leo who is preoccupied with trying to avoid disaster and awaken Mot.