| Anna Torv | Olivia Dunham |
| Joshua Jackson | Peter Bishop |
| Lance Reddick | Phillip Broyles |
| Blair Brown | Nina Sharp
(credit only) |
| Jasika Nicole | Astrid Farnsworth |
| John Noble | Dr. Walter Bishop |
| Geoff Pierson | Arnold McFadden |
| Demore Barnes | Agent Hubert |
| Conrad Coates | Vincent Ames |
| Natassia Malthe | Linda |
| David Richmond-Peck | CSI Detective Kassel |
| Jason Bax | CDC Suit |
| Brendan Beiser | Steve |
| Chris Casillan | Science Center Worker |
| Peter Grasso | Hazmat in Truck |
| Kristian Haas | Mike, Bike Courier |
| Denise Jones | Teacher |
| Megan Leitch | Elaine |
| Tracy Beemer | Female Uniform
(as Tracy McMahon) |
| Kennedy Montano | Small Child |
| Robert Parent | Police Officer |
| Alan Wong | Karl |
| Nicholas W. von Zill | Vandenkemp
(as Nicolas Von Zill) |
| Diana Bang | Nora
(uncredited) |
| Eve Harlow | Cashier
(uncredited) |
| Alberta Mayne | Young Mother
(uncredited) |
| Al Miro | Neal
(uncredited) |
| Sierra Pitkin | Jordan
(uncredited) |
| Simon Charles Tilbe | Glenn Poleson
(uncredited) |