Help a fangirl out?

I'm looking for pop culture examples (TV, movies) of professionals doing their jobs because they're professionals, even though they know -- or strongly believe -- that there's no point to it. An example would be the final episode of Angel. (That might be an example of "the point is that this is all there is," but I hope you get the idea -- you treat the patient because that's your job, not because you think it will help or because you think it makes you especially noble. You investigate the crime not because you're doing justice or because you have a personal stake but because that's what it means to be a cop. Greg House and L&OL's Jack McCoy are, therefore, counterexamples.)

Specific episodes/arcs, please! The point is to have some examples to show students, so the more specific, the better.