| "One Night in October" | |
|---|---|
| Fringe episode | |
 On a multiverse serial killer case, Olivia (left) bluntly reveals to her parallel universe doppelgänger (right) she killed her abusive stepfather (portrayed by Chris Bradford in "Subject 13" and "Lysergic Acid Diethylamide"). | |
| Episode no. | Season 4 Episode 2 |
| Directed by | Brad Anderson |
| Written by | Alison Schapker Monica Owusu-Breen |
| Production code | 3X7002 |
| Original air date | September 30, 2011 |
| Guest appearances | |
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"One Night in October" is the second episode of the fourth season of the Fox science fiction drama television series Fringe, and the series' 67th episode overall. The episode was co-written by Monica Owusu-Breen and Alison Schapker, while Brad Anderson served as director.
In the episode, Olivia is informed by Broyles (Lance Reddick) that the Fringe division of the parallel universe has requested their help to locate a serial killer named John McClennan (John Pyper-Ferguson). With their own universe's John, a university professor, they try to locate the other John with his knowledge of himself while also trying to prevent him of being aware of the alternate universe itself as they cross over. The episode received acclaim from critics who highlighted the performance of Anna Torv's double duty, guest star John Pyper-Ferguson, as well as the exploration of the parallel universe and the use of love and sentimentality that leads to different lifestyle choices.