Many French pop devotees consider the highly influential Serge Gainsbourg the coolest singer of them all. Ironically, he was also thought the sleaziest, a mystifying correlation to some. In any case, calling this latest compilation The Ultimate Best takes marketing gall, considering that at least three dozen Gainsbourg compilations have been released over the years. Then again, that title only shows up on the cover; the original title seems to have been Initials SG, which conjures Initials BB, the album Gainsbourg did with actress Brigitte Bardot when they had their brief fling in 1968. There’s only one duet with Bardot (“Bonnie And Clyde”) among the 23 tracks, many of which are some of the singer’s most popular songs, including the hit version of the infamously prurient “Je T’aime Moi Non Plus” (not the one with BB) and two others with Jane Birkin. Gainsbourg was too multi-faceted an artist to be summed up in a mere single CD, but this is a good introduction to the French dean of debauchery. Booklet includes interesting notes by Sylvie Simmons, author of a book on the man.