The opening and closing musical tracks of Spike Lee's "Inside Man" immediately attracted the attention of film critics and moviegoers alike because Lee chose an unexpected piece of Bollywood music as a curtain-raiser for his urban thriller.

Online discussion boards, particularly iTunes' "Inside Man" soundtrack homepage, were swamped with demands for the single "Chaiyya Chaiyya Bollywood Joint."

Longtime Lee composer Terence Blanchard says the song, which originally was featured in the 1998 Bollywood hit "Dil Se," is in perfect keeping with the director's distinct musical choices.

"To me it goes right back to when Spike did 'Do the Right Thing' and he used (Public Enemy's) 'Fight the Power'," Blanchard says. "He is a serious music lover and he knew ("Chaiyya Chaiyya") would create a unique viewing experience; it sends you off in an unexpected direction thinking in an expanded tonal palette for the picture."

Blanchard lightly rearranged composer AR Rahman's original track for the film by beefing up the song's orchestration with some strings, horns, brass and timpani, and he also tried to extend the musical structure of the song without being redundant.

Then the composer and the director brought in Panjabi MC to add hip-hop lyrics that play on the song's original themes of cultural divides.

The instrumentation also connects with Blanchard's jazzy original score for the film that the song bookends. And though Lee generally gives Blanchard a lot of room to create musical ideas around his images, the way they reached the song choice for "Inside Man" was slightly unusual even by the standards of their long-running relationship. "We hadn't had any musical conversations about the movie until he started to cut the picture together," Blanchard says. "Whereas on (the Golden Globe nominated score for) '25th Hour,' Spike told me to get prepared for wall-to-wall music."

When Blanchard saw a rough cut, the first thing that struck him was its distinct look and Denzel Washington and Clive Owen's performances.

"I said, I know the music has to have an aggressive pulse to it given those characters," Blanchard says. "But it's always interesting working with Spike -- he loves melody."

Of the previous films on which they have worked, Lee always has asked Blanchard for a CD of distinct themes, which the director then assigns to different characters. The same was true but with a twist on "Inside Man."

"Spike picked one of the prettiest themes and gave it to Dalton (Owen's character) who's supposed to be bad guy!" Blanchard laughs. "I said, You sure you want to do that? He always tries to go for some unique and different choices and by doing that he creates a challenging narrative that also helps tell the story."

Blanchard wrote the score over four weeks and recorded it with more than 60 orchestra members for four days at Todd-AO in Los Angeles.

But just days before he was set to record the score, Hurricane Katrina wiped out Blanchard's childhood home in New Orleans. He was unable to find his mother for two weeks.

The composer's story of personal loss will be documented in Lee's upcoming documentary "When the Levees Broke."

"Trust me, it's hard for people to fathom the vastness of the tragedy," Blanchard says. "We have friends who survived, but lost everything and died from broken hearts. Working on the 'Inside Man' score was a Godsend for me. When you hear the Dalton themes in the beginning, it's also what was going on with Katrina in my mind. Music was a great outlet during that period."