I loved this episode, largely because I'm a Star Trek & X-Files fan as well as a fan of detective series. This Who/What dunnit went right up to the wire before the perpetrator was identified (6 mins before the end). It was great to see Walter Koenig (Chekov in the original Star Trek) in another sinister role (as he did with Bester in Babylon 5). Majel Barrett Roddenberry made a welcome addition as an alien abductee & to see Wil Wheaton playing an adult for once (around 7 years after he left Star Trek: The Next Generation) went to show that he is a credible actor (and not just a "child star"). The episode takes the characters, largely, out of the hospital format for once and it's a welcome change - even Dr.s need holidays :D
The pacing of the show was good, and although it seemed illogical for it to be an alien abduction in a detective series, the plot line was credible enough to have even *me* considering that this was how it was going to pan out.