When the Professor, Wolverine, and Storm are away on personal matters, the younger X-Men decide to have a party at the mansion, but a nerdy schoolmate discovers The Danger Room and thinks it's an elaborate video game.
A malfunction in Juggernaut's stasis field leaves the X-Men without adult supervision. Deciding to hold a party, they ditch Scott and Jean in the wilderness. However, things soon get out of control when one of the guests gives himself access to Cerebro and another with hidden sinister intentions.