| Naveen Andrews | Sayid Jarrah |
| Henry Ian Cusick | Desmond Hume |
| Jeremy Davies | Dr. Daniel Faraday
(credit only) |
| Emilie de Ravin | Claire Littleton |
| Michael Emerson | Ben Linus |
| Matthew Fox | Dr. Jack Shephard
(credit only) |
| Jorge Garcia | Hugo 'Hurley' Reyes |
| Josh Holloway | James 'Sawyer' Ford |
| Daniel Dae Kim | Jin-Soo Kwon
(credit only) |
| Yunjin Kim | Sun-Hwa Kwon
(credit only) |
| Ken Leung | Miles Straume |
| Evangeline Lilly | Kate Austen
(credit only) |
| Rebecca Mader | Dr. Charlotte Lewis
(credit only) |
| Elizabeth Mitchell | Dr. Juliet Burke
(credit only) |
| Terry O'Quinn | John Locke |
| Harold Perrineau | Michael Dawson |
| Cynthia Watros | Libby Smith |
| M.C. Gainey | Tom Friendly |
| Anthony Azizi | Omar Idris |
| Blake Bashoff | Karl Martin |
| Grant Bowler | Captain Gault |
| Starletta DuPois | Mrs. Dawson |
| Kevin Durand | Martin Keamy |
| Jeff Fahey | Frank Lapidus |
| Mira Furlan | Danielle Rousseau |
| Tania Raymonde | Alex Rousseau |
| Fisher Stevens | George Minkowski |
| Marsha Thomason | Naomi Dorrit |
| Galyn Görg | Nurse |
| James Locke | Jeff /
Mechanic |
| Bill Ogilvie | Gus /
Pawnbroker
(as William P. Ogilvie) |
| Will Allen | Arturo
(as Francesco Simone) |
| Jill Kuramoto | Female Anchor |
| Malcolm David Kelley | Walt Lloyd
(uncredited) |