Season: 4
Air Date: 9/30/11

Fox's slept-on sci-fi thriller Fringe worked best when it uses its super science-y plot lines and evil genius villains as a device to get down to the simple, basic human themes of choices, consequences, and connections. Early on, when the series introduced a parallel universe where alternate versions of everyone exists (including the main cast members), it added a tantalizing dimension to those weighty, thoughtful themes: What experiences shaped us into the people we are today?

The alternate universe provides the same characters, altered in small or potentially very drastic ways by tiny differing changes in their lives. This is highlighted spectacularly in "One Night in October" in which Earth-2 Fringe Division enlists Earth-1 agents to help them catch a serial killer on their side. In their world, he's a dark, demented murderer who's slain dozens of people; in Earth-1 he has a psychology degree and specializes in serial-killer profiling. Earth-2 Fringe assumes that he'll naturally be able to profile himself, but the question at the heart of episode is: What did Earth-1 John McClennan have in his life that kept that same darkness at bay?

"October" features the necessary cool, yet unsettling case-of-the-week hook—Earth-2 John freezes his victims' brains from the inside—but the episode really soars when both Johns meet, and recount a pivotal night in their lives following an October fair that changed everything for them, but in drastically different ways with drastically different outcomes. In the end it drives home Fringe's overall series mantra: love and emotional connections are stronger than any type of weird science.