The film, directed by Louie Psihoyos, contains footage of dolphins being brutally killed (be warned if you don't like to see such things) and points out that meat from the mammals has high levels of toxic methyl mercury.
(wait a while to download if it buffers too much)
J. Ralph - The Cove (Original Motion Picture Score)
See also End Of The Line
How we will see the end of most seafood by 2048