The ending of “Lost” explained: What really happened on the island?

Entertainment Weekly answers lingering questions about the finale, from the split timelines to the symbolism in the last sequence.

Warning: This article contains spoilers for Lost, season 6, episode 17, "The End."

Lost had one of the most controversial series finales of all time, blowing some fans away while leaving others angrily scratching their heads. But ABC’s sci-fi stunner, created by Jeffrey Lieber, J. J. Abrams, and Damon Lindelof, wasn’t always so hotly contested…

The Emmy-winning series was an instant hit after its iconic pilot in September 2004, seeing Oceanic Flight 815 crash on a (supposedly) deserted island. Lost soon evolved from a standard survival tale into a twisty mind-bender with various mysteries woven throughout its six seasons, from the Others to the Dharma Initiative to the onset of time travel.

But when “The End” aired on May 23, 2010, many viewers had more questions than answers. What’s the deal with the split timelines? Why is everybody in a church all of a sudden? And were the characters really dead the whole time?

Entertainment Weekly is taking a hard look at the finale to answer all of these burning questions and more. Here is the ending of Lost, explained.

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Do we ever find out what the island is?

The answer is a resounding “sort of.” The show provides several abstract theories but never concretely explains what the island is.

Here’s what we know: The island is a place with mystical properties, including the ability to heal (e.g. John Locke’s paralysis) and manipulate time and space (the time-jumping in season 5). It’s also the battleground for a cosmic struggle between two opposing forces represented by Jacob (Mark Pellegrino) and the “Man in Black” (a.k.a. the Smoke Monster, played by Titus Welliver). Jacob is the island's protector, while the Man in Black represents chaos and destruction. This conflict drives much of the show’s overarching mythology, with the island acting as a sort of prison for the Man in Black, who is trying to escape.

It also contains a mysterious and powerful energy, often referred to as the "Heart of the Island." This glowing cave of light is linked to the island’s mystical properties and is believed to be the source of life, death, and rebirth. It’s described as a “cork” holding back a malevolent force that, if released, could free the Man in Black and bring darkness to the world.

Protecting this energy is Jacob’s primary role. When Desmond (Henry Ian Cusick) enters the Heart of the Island, it’s revealed that the energy can be manipulated to catastrophic effect.

Related: Lost: How binging the series with my son brought us closer

What happened on the island?

Previously, Jacob explained that the passengers of Oceanic Flight 815 were brought to the island so that one of them could become its protector, taking over Jacob's role. The list of candidates was revealed in the lighthouse and in the cave, where their names were written with corresponding numbers that recurred throughout the series (4, 8, 15, 16, 23, 42). As the candidates failed or died, Jacob would cross off their names, narrowing down the list to a final few. In the end, Jack takes the role and agrees to protect the island from the Man in Black.

During the series finale, the Man in Black, who is now in Locke's (Terry O’Quinn) body, makes his final attempt to escape. He brings Desmond to the Heart of the Island so he can turn off its source of power. Jack helps the Man in Black because he believes "uncorking" the power source is the key to killing him once and for all.

Desmond successfully uncorks a stone plug at the island's core and extinguishes the light. However, this action causes earthquakes, indicating that the island is on the verge of destruction and that the energy source is critical to keeping it intact.

Jack and the Man in Black have an epic battle, and Jack prevails. However, the uncorking makes the Man in Black mortal, and he dies. Jack, knowing that the island must be saved, takes it upon himself to restore the light.

He tells Kate (Evangeline Lilly), Sawyer (Josh Holloway), and Claire (Emilie de Ravin) to escape on the Ajira plane while he stays behind. Jack re-enters the cave, finds Desmond, and sacrifices himself by replacing the stone cork, which reignites the light and stabilizes the island. As a result, Jack fulfills his role as the protector, but it costs him his life.

Jack then realizes he is dying from his injuries. He passes the torch of island protector to Hurley (Jorge Garcia), who reluctantly accepts this role. Ben (Michael Emerson), who had served Jacob for years, offers to stay and help Hurley as his advisor, and Hurley appoints him as his second-in-command.

What’s up with the “flash sideways” timeline?

In a controversial move, the final season is split into two timelines. The first timeline follows the events on the island, continuing from previous seasons as the Oceanic Six face the Man in Black and the impending destruction of the island.

The second timeline, referred to as the "flash sideways," presents an alternate reality where the plane never crashes and the characters live seemingly different lives, though their paths still intersect in significant ways. Sawyer becomes a cop instead of a criminal; Ben becomes a teacher with Alex (Tania Raymonde) as one of his students; Kate befriends Claire while on the run. During the series finale, many characters experience visions of their lives in the original timeline triggered by reminders of the island.

After his death, Jack arrives at a church in the flash sideways featuring symbols from multiple religions. He reunites with his dead father, Dr. Christian Shepherd (a very on-the-nose name), who explains that they're in a kind of purgatory. Since the survivor’s time on the island was the most important part of their lives, they created a place where they could find each other after death, irrespective of when they each died. Now that they’re reunited, they can move on to the afterlife together.

Related: How Sun and Jin's relationship went from problematic to transcendent on Lost

Which characters moved on to the afterlife (and with whom)?

In the end, almost all of Lost’s central characters are reunited in the church and paired off with their soulmates, including Jack and Kate, Sawyer and Juliet, and Charlie (Dominic Monaghan) and Claire. Fans were particularly vocal about Sayid (Naveen Andrews) ending up with Shannon (Maggie Grace) in the afterlife rather than Nadia (Andrea Gabriel), even though the character’s love for Nadia served as his motivation for the majority of the series.

However, not everyone moved on. Ben chose to stay behind, feeling unworthy of doing so just yet. This decision was a point of growth for his character, hinting at his ongoing need for redemption. Several major characters weren’t seen in the church, including Mr. Eko (Adewale Akinnuoye-Agbaje), Michael (Harold Perrineau), Walt (Malcolm David Kelley), and Ana Lucia (Michelle Rodriguez). There were also characters seen in the flash sideways world who did not appear in the church, like Alex.

Were they dead the whole time?

No. During earlier seasons of Lost, it was fair to wonder whether the passengers of Oceanic Flight 815 were all dead and stranded in some kind of limbo. However, as the story progressed, and especially when characters started leaving the island and then screaming “We have to go back!”, it became evident that they were in a real place. In fact, since the finale aired, Lost creators have clarified that the events on the island were real.

So where did the confusion come from? Mostly the flash sideways timeline introduced in the final season. The characters are all dead in that purgatory, but they only went there when they died in the original timeline; none of them died in the initial plane crash, and everything that happened on the island was real.

After the last episode, ABC aired footage of the plane wreckage as a callback to the pilot, which led some to believe that everyone was dead from the beginning. This was not the case; the characters lived through real events on the island, and the flash sideways was a separate spiritual journey.

What does the last shot mean?

The final moments of Lost mirror the opening sequence in the pilot. We see Jack lying on the ground in the bamboo forest, his eyes closing as he succumbs to his injuries. It's a poignant end to Jack's journey, bringing his story full circle and marking the conclusion of his role as the island's protector.

In the final shot, there's also a subtle but poignant detail: the inclusion of Walt’s dog, Vincent, who has been a constant throughout the series. He lies next to Jack as he dies, symbolizing the continuity and connection between the characters’ past and present. The dog’s presence suggests that the relationships and bonds formed on the island endure beyond death.

Read the original article on Entertainment Weekly.