To be able to finally realize their childhood dream, 3 young men plan to rob a bank. Nishiyama, the leader, Takamura, a very self contained guy and Fujimoto, an otaku obsessed by an anime called Space Travelers. Their plan is very simple, enter the bank at the closing time, take the money and leave within 5 minutes. But unfortunately for them, their plan got screwed. Not able to reach the money and read moresurrounded by cops, they are stuck in the bank. They then decide to use the remaining customers and staff as hostages to gather some time to plan an escape, but they soon realize that an escape is almost impossible.
With the time passing, the hostages begin to sympathize with the three robbers and decide to help them. Nishiyama gets an idea that could help them, try to fool the police into thinking that they are more than what they are in reality. They will all decide to personalize a member of the favorite anime of Fujimoto and call the whole group The Space Travelers. Strangely every one has a character that really correspond to their personality and they will soon begin to develop a real association to their character, forgetting their own personality, as they all begin to be more active in the new improvised band of bank robbers. This matter doesn't help the police at all, confusing them even more as they try to solve that delicate hostage situation.