It's pretty obvious why Doogie Howser's Neil Patrick Harris took the starring role in A Stranger in the Family: This is one of those all-out, emotional roles that give a sitcom actor a chance to stretch long-constrained acting muscles. The problem is, an actor's showcase is frequently too one-sided to make for good drama. So it is with Stranger, in which Harris plays a teen who suffers from amnesia after a minor car accident. This isn't just your ordinary ''Gee, what's my name?'' TV-style amnesia: Harris' Steve Thompson has forgotten how to talk, how to dress and feed himself, how to read and write he's a perfectly healthy, normal-on-the-outside, incapacitated person. A Stranger in the Family centers around Steve's rehabilitation and how it affects his family particularly his mother, played by Good & Evil's Teri Garr.
In the early scenes, as Steve's mother discovers the extent of her son's disabilities, Garr is terrific emotional yet contained, furious at the doctors who speak to her condescendingly yet abruptly tender with her son and husband (Randle Mell). Most of the movie, however, revolves around teaching Steve to speak and the ways in which his parents coax thoughts and feelings out of him. Harris never overdoes it, even when the screenplay by Rene Balcer and Hal Sitowitz leads him into tear-jerk territory with scenes of him staring blankly while a doctor asks, ''Do you know what love is?'' Despite admirable restraint from both Harris and Garr, Stranger devolves into wet melodrama. C-