It wasn't a hit because........
I just saw this film again the other night after maybe 10 years.
It should have been a bigger hit than it was.
I think a few things prevented it from being a huge hit.
Lack of star power.
Not enough of Jennifer Beals.
A bit too laid back.
Some oddball casting.
Weak pay-off.
I had forgotten why the Jennifer Beals character was even in the film and why all the events were occurring. The pay-off at the end did not justify all the action we had seen on the screen. The film is very "Chinatown"ish, but it didn't have a big pay-off like CHINATOWN did.
Some people on this board have also suggested that the film may have been passed over by white viewers and I think that may be true. I don't know how the film was marketed when it was released, but the film has no white stars with the partial exception of Jennifer Beals. Or white folks may have thought it was a 'black film' for black audiences.
Oh, well....too late now.