The Lost World - Season 3 - Eps 21: Trapped
A peaceful day of exploration turns deadly when a sudden explosion traps Marguerite and Roxton in an underground chamber. Their only hope for escape is Challenger, but the same explosion has left him with no memory of who he is, or what has happened to his friends. Meanwhile, a contest of friendly rivalry between Veronica and Finn leads to an enigmatic discovery at the Treehouse, as another memory from Veronica's childhood is literally uncovered. Faced with certain death, Roxton and Marguerite reveal emotions best left buried, so that even if they do survive their ordeal, there's a chance their relationship will not.
About The Lost World

Title: The Lost World
First Air Date: 1999-04-03
Last Air Date: 2002-05-13
Status: Canceled
Rating: 7.2/10 (from 116 votes)
Language: EN
Seasons: 4
Total Episodes: 66
Network: Syndication
Genres: Action & Adventure, Drama
Production Companies: Coote Hayes Productions, Telescene Film Group Productions, St. Clare Entertainment
Synopsis
Early 20th-century adventurers find themselves fighting for survival after their hot-air balloon crashes into a remote part of the Amazon, stranding them on a prehistoric plateau.
Cast

Peter McCauley
Professor George Challenger

Rachel Blakely
Marguerite Krux

William Snow
Lord John Roxton

Jennifer O'Dell
Veronica Layton