JACK'S LACK OF SLEEP BRINGS HIM TO THE EDGE OF DELIRIUM, BOONE GETS TRAPPED IN A DANGEROUS RIPTIDE, AND CLAIRE'S HEALTH TAKES A TURN FOR THE WORSE, ON ABC'S "LOST"

Veronica Hamel ("Hill Street Blues") Guest Stars as Jack's Mother

"White Rabbit" - Jack is near delirious from lack of sleep and struggles to overcome the haunting events that brought him to Australia and, subsequently, to the island. Meanwhile, Boone gets caught in a treacherous riptide, the pregnant Claire's health takes a bad turn, and a thief may have stolen the last bottles of water. Veronica Hamel ("Hill Street Blues") guest stars as Jack's mother, on "Lost," WEDNESDAY, OCTOBER 20 (8:00-9:00 p.m., ET), on the ABC Television Network.

"Lost" stars Naveen Andrews as Sayid, Matthew Fox as Jack, Jorge Garcia as Hurley, Maggie Grace as Shannon, Josh Holloway as Sawyer, Malcolm David Kelley as Walt, Daniel Dae Kim as Jin, Yunjin Kim as Sun, Evangeline Lilly as Kate, Dominic Monaghan as Charlie, Terry O'Quinn as Locke, Harold Perrineau as Michael and Ian Somerhalder as Boone.

Guest starring are Emilie de Ravin as Claire, John O'Hara as young Jack, John Terry as Dr. Shephard, Sev Palmer as meathead, Veronica Hamel as Margo, Andy Trask as hotel manager, Geoff Heise as doctor and Meilinda Soerjoko as ticket agent.

"White Rabbit" was written by Christian Taylor and directed by Kevin Hooks.

"Lost" is broadcast in 720 Progressive (720P), ABC's selected HDTV format, with 5.1-channel surround sound.

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