21 year old Kohei Tabuchi, known as Bussan to his friends, is told he has just months to live. When he decides to do something daring his friend Ani provides him with perfect target - their grotesque baseball coach Nekota who is working as a small time crook for Yakuza wannabee Mr Yamaguchi. Bussan gathers his closest friends (along with rival Bambi and oddball Uchi who overhears), to take part in a scheme to get one over on their corrupt coach but he soon has to own up to them about his condition.
Yamaguchi's bag containing his gun is stolen and after discovering the gangs secret he forces them to track it down and steal it back before it is used for anything. Unfortunately all the signs point to the original theif being Ozzy.
A dejected Ani gets into gambling debts and Nekota takes him to a powerful businessman, Mr Komine, to help pay it off. However, Komine does not want to be paid back in yen forcing Ani to go into hiding to avoid a watery grave or even worse, a bumming. An outraged Bussan rallies the Cats to try and raise the cash to help out his friend but Komine isn't going to take no for an answer. Meanwhile Bambi arranges a group date to try and hook up with Moko, but Uchi is the only one who gets lucky - or is he?
Masta's kleptomaniac cousin comes to visit and when Uchi accidentally informs her of the Cats Eye's activities she decides to use it as a cover to rob the whole town. Meanwhile the Cats all enter the Mr Kisarazu competition but Uchi accidentally tampers with the results as the boys set out to clear their names and return the stolen goods as the winner's parade takes place.
Bussan's hero Sho Aikawa turns up in Kisarazu to shoot a movie, prompting Bussan to arrange a baseball match against him with Ozzy as their guest pitcher. Nekota starts dealing toluene but enlists Ozzy to do it for him when bike gangs start getting involved and he loses his nerve, however when Ozzy refuses to be paid for it Nekota is unaware he has revenge in mind and has passed the job on to Uchi. Ani convinces the Cats to steal bikes from the toluene gangs but when they are caught it all ends in tragedy.
Ozzy's body is found, sending the whole town of Kisarazu into mourning. A guilty Nekota springs a revenge attack of his associates landing himself in jail but from behind bars he sets the boys a bizarre mission to avenge Ozzy's death.
Bussan discovers that his father's girlfriend Rose is the mother of rock band Kishidan and uses this to try and land himself a support gig with the rest of the gang in exchange for helping them out with their lowlife manager. Bambi's desire to be the lead singer frustrates Bussan and Moko's continual harrassment of him leads to a rift between the three. Can Bambi save Moko from accidentally starring in a porn film before it's too late?
Bussan's condition grows worse as he isolates himself from his friends and spends his nights alone talking to Ozzy's memorial statue. When Masta, Ani and Mr Yamaguchi are all conned out of money by the same girl, Misuki Asari, he decides to take action but in his increasingly erratic state he doesn't count on falling in love with her. Asari soon reveals she wants Bussan to steal something for her - but is she really being genuine this time or merely pulling a con on him too?
The Cats decide the only way to take Bussan to Tokyo is to kidnap him, but once there his strange behavior embarrasses them. A chance encounter with an old friend, Little Yamada, who has become a big league baseball player sends Bussan and his friends on a series of missions to keep an old promise but it all proves too much for him as his time runs out.