For most of season 6, the sideways stories function as an extended narrative game of “What If?” giving us a chance to imagine different narrative arcs for our beloved castaways had they never crashed on the island and been swayed by Jacob’s mystical influence. As discussed in chapter 9, Lost’s transmedia extensions typically operated with a “What Is” logic of canon or pseudo-canon, but it is within the series itself that Lost most directly explores a “What If?” impulse via this sideways realm.… As discussed in chapter 4, even though Lost is most renowned for its elaborate enigmas and ludic plotting, its producers consider its characters and their relationships as the program’s core appeal, and thus it is not surprising that the final season’s narrative innovation prioritized emotional payoffs regarding characters over plot coherence.
An unsympathetic reading is that Lost’s sideways storyline is a cheat, designed to mislead the audience into assuming it was a parallel universe in which the island did not exist but revealed in the end to be internally incoherent without resorting to a higher power. My more sympathetic reading acknowledges that it is a cheat but views the payoff as more thematically coherent than narratively motivated. As viewers, we hope that we got to spend the most important parts of these characters’ lives with them and want to believe that our connection to them mattered. We also enjoyed spinning theories in search of coherence within a fantasy narrative that often made little logical sense, and the sideways world was our last opportunity to play such interpretive games. The sideways world is Lost’s embedded metafiction, the rumination on why we enjoyed spending time with these characters, a celebration of the series’s shaggy mélange of genre influences and diverting puzzles, and a delivery system of moments of emotional engagement to pierce through its silly but fun pulpy narrative. Looking back from the finale, it becomes clear that the entirety of season 6 worked to refocus our attention on the characters and away from the mythology, for both the characters themselves and the viewers, providing the wish fulfillment of a happy ending and the joy of returning departed friends and reunited relationships without the baggage of the island’s mysteries. In the finale’s closing moments, Christian Shephard is talking to us viewers, saying that this world is what we would make if we imagined new “What If?” tales for our heroes, functioning as a form of embedded fan fiction. The fact that it cheats to let us spend more time with dead characters and debate possible theories on Lostpedia does not matter—and ultimately the purpose of fiction is not to pass a test of logical coherence but to keep us emotionally engaged and entertained.