I think perhaps that's what the movie is about. Gould and Sutherland and the members of their merry band of pranksters are offended because the Army regulars don't feel deeply enough. "Hot Lips" is concerned with protocol, but not with war. And so the surgeons, dancing on the brink of crack-ups, dedicate themselves to making her feel something. Her façade offends them; no one could be unaffected by the work of this hospital, but she is. And so if they can crack her defenses and reduce her to their own level of dedicated cynicism, the number of suffering human beings in the camp will go up by one. And even if they fail, they can have a hell of a lot of fun trying. Also, of course, it's a distraction.
Through it all, though, James is a delight to watch as Lizzie. If you saw her last year in Kenneth Branagh ’s “Cinderella,” you know how hugely appealing she can be. Here, she’s playing a very different kind of iconic figure, but in both cases there’s something pure about her screen presence that makes her seem accessible and true. And she has decent chemistry with Riley as the arrogant, abrasive Darcy—but then again, several of their key exchanges take place within the context of some sort of physical fight, either with each other or against the stumbling, mumbling undead, which detracts from their inherent romantic tension rather than enhancing it.