| Anna Torv | Alternate Olivia Dunham |
| Joshua Jackson | Peter Bishop
(credit only) |
| Lance Reddick | Phillip Broyles
(credit only) |
| Blair Brown | Nina Sharp
(credit only) |
| Jasika Nicole | Alternate Astrid Farnsworth |
| John Noble | Dr. Walter Bishop /
Walternate |
| Michael Cerveris | September |
| Seth Gabel | Alternate Lincoln Lee |
| Amy Madigan | Marilyn Dunham |
| Andre Royo | Henry Arliss Higgins |
| Kendall Cross | Nurse Joyce |
| Darcy Laurie | Doctor |
| Ryan McDonald | Brandon Fayette |
| Françoise Yip | Dr. Rosa Oporto
(as Francoise Yip) |
| Kirk Acevedo | Alternate Charlie Francis |
| Heather Doerksen | Major Warner |
| Randal Edwards | Fringe Agent #2 |
| Ben Geldreich | Kidnapper #2 |
| Peter Hanlon | Doctor #1 |
| Nicole Hombrebueno | Young Woman |
| Achara Kirk | Fringe Agent #1 |
| Courtney Lancaster | Pediatric Nurse |
| Matthew Thiessen | Doctor #2 |
| Barry Ostash | Young Man
(uncredited) |