"School Reunion," by Toby Whithouse, was the "very special episode" that brought back Elisabeth Sladen as Sarah Jane Smith, perhaps the most popular of all the Doctor's companions down through the years. She and her robot dog, K9 were last seen more than 20 years ago when the Doctor left both high and dry. Abandoned.

Boy, is she pissed off.

The episode cleverly mythologizes what, at the time, was a business reality: the producers recast and, as was the custom in those days, didn't do too much on-camera to explain it. This is turned intlo a powerful insight into the Doctor's character, with eye-opening implications for Rose: he can't bear to watch his (mortal) companions grow old and die.

Rose is understandably upset by this revelation. Will he do to her what he did to Sarah Jane?

Criminally, they went nowhere with this potential schism between them. (It's especially wrong given that they knew Billie Piper was quitting at the end of the season.)

Plotwise, though, "School Reunion" pretty much sucked. The Doctor and Rose (and Sarah Jane, for that matter) are all undercover at a school where kids are "getting sick." There are strange lights in the sky, a nefarious plan to take over the universe--MWAH HA HA--and an evil headmaster (the usually wonderful Tony Head) who likes to hiss at the camera for no apparent reason. *Yawn*

Still, it would be nice to see more of Liz Sladen. (It would be great if The Doctor sought her out in his grief over losing Rose--say, in the next Christmas Special--but, sadly, it doesn't look like that's in the cards.)