K-9 and Company

Airing a week before Peter Davison's debut as the Fifth Doctor, this little special brought back Doctor Who fan favorites Sarah Jane Smith and K-9.

Although K-9 and Company was conceived as a spinoff of Doctor Who, it wasn't picked up, airing as a single special, also called "A Girl's Best Friend". Nonetheless, it is part of the Whoniverse Canon and many elements of it define the character of Sarah Jane Smith after her departure in The Hand of Fear. More than 25 years later, a second, more successful spinoff for Sarah Jane was made in The Sarah Jane Adventures, with K-9 making occasional appearances. Subsequently, K-9 also got his own show (in different incarnations, however).

Sarah Jane Smith spends the Christmas holiday at her Aunt Lavinia's house in Moreton Harwood to watch her ward, Brendan Richards. In the house, Sarah Jane spots a large crate that was left in the attic for a few years. Inside is K-9 Mark III, a present from the Doctor.

There's also a cult going around doing nasty cult stuff, like kidnapping Brendan. Sarah Jane and K-9 investigate and find out that almost everyone in town is a part of this cult, called the Cult of Hecate. At night, the Cult of Hecate prepare Brendan as a sacrifice for the Winter Solstice, but Sarah Jane and K-9 save him just in the nick of time.

That's pretty much it really. Can you imagine what a full series would be like?

Tropes

 * Annoying Laugh: Brendan's laugh is described by Sarah Jane as "honking".
 * Billing Displacement / Spotlight-Stealing Title: A confusing case. Based on the title, one would assume that K-9 is the main character and end up wondering why Elisabeth Sladen is credited first in the title sequence instead of John Leeson. This really is Sarah Jane's show, but K-9 gets his name in the title instead.
 * Black Cloak
 * Christmas Episode
 * Cult: And almost every townsperson (at least the ones we see) is in it.
 * Distressed Dude: Brendan
 * Just in Time: Sarah Jane and K-9 make it in time to stop Brendan's sacrifice. K-9 goes full salvo.
 * The Nth Doctor: Sarah Jane's K-9 is a Mark III version, whereas the Doctor had owned versions I and II.
 * One Episode Wonder
 * Race Against the Clock
 * Secret Circle of Secrets
 * Spiritual Predecessor: To The Sarah Jane Adventures.
 * Took a Level In Badass: Looks like Sarah Jane knows martial arts now.
 * Town with a Dark Secret
 * You Look Familiar: Bill Fraser, who played Commander Pollock, was previously General Grugger in Meglos, but here he has no glorious beard.