I have no knowledge of the film HEAT, but the general point about Mann is viable.
“..Mann’s heroes almost always end up alone and isolated. However, they are not simply alone, but alone because they adopt a sense of duty that brooks no compromise with the exigencies of society or even survival.” – Their ethical drive leads them to refuse the false satisfaction that the symbolic order offers. Their ethos consists in a drive to abandon everything that would confine them within a symbolic identity. .. While watching a film such as Heat, our enjoyment derives in large part from this excess, which allows us to see the enjoyment in duty itself, ..the enjoyment ..for the sake of duty rather than for any pathological motivation. ..The film also makes clear that this enjoyment does not imply happiness.
The Real Gaze. – TODD MCGOWAN – On the neurotic side of film heroes