Bill Murray stars as Steve Zissou, a world-famous oceanographer who films documentaries of his adventures aboard the ship Bellafonte. It's clear that his better days and films are behind him; his marriage is tense and he's out of funding for his next film. When the movie opens, Zissou is at the premiere of his latest documentary in Italy. During the screening of the documentary, the audience discovers Esteban (Seymour Cassel) - a member of Team Zissou, and Steve's best friend - was killed by a large jaguar shark.
During the premiere, we meet other members of Zissou's oceanography team : Klaus Daimler (Willem Dafoe), a moody German; Pele (Seu Jorge), who sings and plays the guitar; and Eleanor Zissou (Anjelica Huston), Steve's estranged wife.
Steve and Eleanor have a successful business relationship, and do seem to love each other despite their current rough patch (supposedly revolving around Steve's infidelities and Eleanor's relationship with ex-husband, and rival film maker, Alistair Hennesay)(Jeff Goldblum). Steve's mistress shows up at the premiere while cocktails are being serve