| Matthew Fox | Dr. Jack Shephard |
| Terry O'Quinn | John Locke /
Man in Black |
| Evangeline Lilly | Kate Austen |
| Josh Holloway | James 'Sawyer' Ford |
| Naveen Andrews | Sayid Jarrah |
| Henry Ian Cusick | Desmond Hume |
| Daniel Dae Kim | Jin-Soo Kwon |
| Yunjin Kim | Sun-Hwa Kwon |
| Michael Emerson | Ben Linus |
| Jorge Garcia | Hugo 'Hurley' Reyes |
| Emilie de Ravin | Claire Littleton
(credit only) |
| Elizabeth Mitchell | Dr. Juliet Burke |
| Nestor Carbonell | Richard Alpert |
| Ken Leung | Miles Straume |
| Zuleikha Robinson | Ilana Verdansky |
| Sam Anderson | Bernard Nadler |
| L. Scott Caldwell | Rose Nadler |
| Brad William Henke | Bram |
| Kimberley Joseph | Cindy Chandler |
| Fredric Lehne | Marshal Edward Mars |
| Jeff Fahey | Frank Lapidus |
| Dominic Monaghan | Charlie Pace |
| Mark Pellegrino | Jacob |
| Daniel Roebuck | Dr. Leslie Arzt |
| Ian Somerhalder | Boone Carlyle |
| Sean Whalen | Neil 'Frogurt' |
| Greg Grunberg | Pilot Seth Norris
(voice) |
| Shawn Lathrop | Flight Attendant |
| Mark Ahsing | Customs Officer
(uncredited) |
| Dave Coennen | Agent Smalley
(uncredited) |
| Kesha Diodato | Agent Anne
(uncredited) |
| Mickey Graue | Zach
(uncredited) |
| Kiersten Havelock | Emma
(uncredited) |
| John Hawkes | Lennon
(uncredited) |
| Kelly Kraynek | Woman in Bathroom
(uncredited) |
| David H. Lawrence XVII | Cab Driver
(uncredited) |
| Troy Manandic | Airplane Passenger
(uncredited) |
| Hiroyuki Sanada | Dogen
(uncredited) |
| Percival Scott III | Security Officer
(uncredited) |
| Troy Vincent | Oceanic Rep
(uncredited) |