| dbp:caption
|
- Seth Gabel, a guest star during seasons 2 and 3, joined Fringe as a series regular in season 4 as agent Lincoln Lee. He reappears in season 5. (en)
- Michael Cerveris plays September, one of the bald-headed Observers, and appears several times throughout the series. (en)
- Leonard Nimoy portrays William Bell, Walter's associate, both as a live action character in seasons 1, 2, and 4, and voicing an animated Bell in season 3. (en)
- The "Prime Universe" title card used for seasons 1–3. (en)
- Mark Valley played Olivia's partner and lover, John Scott, in the first season. (en)
|