devoid of passion

i love this movie to death, and i saw it for the umpteenth time with my boyfriend last night. while he enjoyed the film, he said the story was devoid of passion. his argument was as follows: the driving force behind the film is the love between maqbool and the mistress, but the film fails to convey the passion and the love the two had for one another; maqbool's inner conflict comes across quite apparent, but the love and the passion, not so much.

i argued that the point was a matter of personal perception - the portrayal is subtle; there are no over-the-top or kitsch scenes in which the two express their undying love. with that said, the climax was heart-wrenching and beautiful, albeit at the very end of the film. what makes this film different, also, from other gangster-cop sagas is that there's no gratuitous violence or drama. but i would say this: it wouldn't have hurt if the 'love' part of the story had been more fleshed out; if the film itself has been more 'shakespearean' as opposed to more focussed on following the motions of a typical underworld ganglord.

however, if an adaptation from text to screen is planted in a particular scenario or situation (ie the underworld), then contrivances and the subsequent derivation of parallels are imminent. we ended the argument with the conclusion that this whole subgenre of contrived adaptation wasn't his thing.

ultimately my questions are these: can an adaptation from text to screen not be contrived (between the two of us we know that adaptations specifically not in-situ are always contrived), and was the movie devoid of passion (why does maqbool kill his gangmaster - for love or power)?