It's hard to imagine a time when Doctor Who wasn't on television, but there was a long break between the 7th and 8th Doctor, as well as between the 8th and 9th Doctor. During that break, fans of the series turned to Doctor Who books, audio dramas and comic books to get their time and space traveling fix.

There were also direct-to-video spin-off series created by fans, thanks to the BBC's lack of copyright on characters that appeared on the series. One of the most popular of those fan-made series, Downtime, celebrates its 20th anniversary this year with a DVD release.

Downtime featured long-time Doctor Who character Brigadier Lethbridge-Stewart, as portrayed by Nicholas Courtney, along with former companions to the Doctor Sarah Jane Smith (Elisabeth Sladen) and Victoria Waterfield (Deborah Watling). Directing the film was Chris Barry, who also served as director on the BBC series.

Here's the official synopsis of Downtime:

"Many years after trying to take over the world, the Great Intelligence is back once more. Brigadier Lethbridge-Stewart, now retired, and Sarah Jane Smith have to stop it, but this time without the Doctor's help. Victoria Waterfield and Professor Travers have also returned, but whose side are they really on?"

Fans of the new Doctor Who series know the Great Intelligence as voiced by actor Sir Ian McKellan in the 11th Doctor episodes "The Snowmen," "The Bells of St. John," and "The Name of the Doctor." The Great Intelligence also played a part in classic episodes, however, including "The Abominable Snowmen" and "The Web of Fear."

The fan-created Downtime was so popular, though, that it also saw an adaptation in the Doctor Who novels by Virgin Publishing.

Perhaps the most interesting character to make a first appearance in Downtime is the Brigadier's daughter, Kate Lethbridge-Stewart, a character who has become popular on the new series. In Downtime, actress Beverely Cressman played her, although new Who fans are more familiar with Jemma Redgrave's version of the character, which made it canon.

Downtime is available now on DVD on Amazon UK. There's no word yet if it will see a North American release. It's a must-have for diehard fans of Doctor Who.

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