The series is loosely based on Sir Arthur Conan Doyle's 1912 novel The Lost World, though it takes many liberties with the source material, setting the story with the party stranded starting in 1919.

The show was cancelled in 2002 after funding for a planned fourth season fell through, leaving the final episode on an unresolved cliffhanger.

Producers later revealed detailed plans for the unproduced fourth and fifth seasons, which would have introduced mystical elements like the Trion artifact, revealed Marguerite as a descendant of the druid priestess Morrighan, and confirmed Professor Summerlee was alive and living in Avalon.

The unproduced fourth season would have featured guest appearances by two other Arthur Conan Doyle characters, Sherlock Holmes and Professor James Moriarty.

The planned conclusion would have revealed that Finn was actually Malone's great-great-granddaughter, descended from the Amazon character Phoebe (also played by Lara Cox), and would have ended with Challenger's group accidentally teleporting forward in time to 2005 London using Challenger's teleportation invention.

The pilot television movie, originally 93 minutes long, was edited down and split into the first two episodes of the series, 'The Journey Begins' and 'Stranded'.

A Smilodon (saber-toothed cat) was originally intended to appear as a recurring animal on the show, but this plan was cut and only a dead Smilodon ultimately appeared, in the episode 'Blood Lust'.

The original pay-per-view broadcast of the series on DirecTV in 1999 was uncensored and contained nudity and extended scenes, unlike the edited syndicated television and DVD versions.