Bruce Springsteen may be the Boss, but on his latest project he was just a hired hand. He wrote the closing song for director John Sayles' ''Limbo,'' which will premiere at the Cannes film festival on Saturday. You can just imagine Sayles' instruction to his buddy, Bruce: ''Uh, can you write me a song that'll calm the audience down and have them leave the theater not hating my guts for not giving them an ending?''
Sayles chuckles at that scenario. ''No, we didn't get that specific about it,'' he tells EW Online. ''Mostly I told him that because of the ending of the movie, the lyrics couldn't indicate something too happy or too sad, because we want to leave the audience in this kind of tantalizing ambiguity -- so they had to be in some ways neutral, but very emotional.''
Neutral but emotional... sounds like every songwriter's dream assignment, all right. But Springsteen's falsetto-powered song manages to summarize the romantic drama, which has David Strathairn and Mary Elizabeth Mastrantonio tentatively falling for each other in urban Alaska, only to find their lives -- and love -- in danger on a remote wilderness island.
''There is something slightly strange about the song, a little bit eerie, a little otherworldly,'' says Sayles, admiringly. ''One of the nice things about the lyrics is that it's a song about risk and commitment, and that's really two of the main things the movie is about. Specifically, the idea of 'If you do this for me, I'm going to commit myself to you... Lift me up, and I'll fall with you.' And a fall can be scary, you know.''
Springsteen and Sayles have a long history together. ''Limbo'' is only the veteran indie filmmaker's second studio movie; the first was 1983's ''Baby, It's You,'' which also marked the first time he used Bruce's music. Up to that point, the rocker had turned down all requests to have his songs appropriated for the movies -- ''he controls his own music, which is unusual,'' Sayles notes -- but Springsteen respected the director enough to approve the use of ''Adam Raised a Cain'' and several other existing tracks. He then hired Sayles to shoot his ''Glory Days,'' ''I'm on Fire,'' and ''Born in the U.S.A.'' videos.
Of course there's other music in ''Limbo,'' including songs by Richard Thompson and Tom Waits, which are sung by Mastrantonio (''Robin Hood: Prince of Thieves''), who plays a lounge singer. ''I had not actually heard her sing when I decided this would be a good part for her,'' Sayles admits. But his hunch paid off when he was ''thrilled'' with the actress' singing voice, and he even opted to have her sing live on camera rather than lip-synch. ''There's a lot of stuff in the script about how emotional singing is for her, and I wanted her to be able to really play the moment.''