If you haven't watched "Lost" since the days of flashbacks, the Hatch, Henry Gale and Mr. Eko, you won't believe where the story went from there:
Flash-forwards! Time travel! Castaways leaving the island - and coming back! Hurley shedding the pounds! (OK, that last one still hasn't happened.)
What began as a drama about island survival has become an intricate sci-fi mystery that excites its rabid fans on both visceral and intellectual levels, putting an action-packed veneer on a story that draws upon philosophy, mythology, history and quantum physics.
Producers Damon Lindelof and Carlton Cuse promise the show's sixth and final season, which begins 7 p.m. Tuesday, Feb. 2, with a one-hour retrospective and a two-hour premiere episode, will answer many fan questions - but not all of them. "That would be too pedantic," Cuse said Jan. 12 during an ABC press event.
But before we look ahead to the answers of Season 6, we should review the questions of Season 5.
How we got here
Season 5 ended with the cast back on the mysterious island in two factions separated by 30 years, thanks to an as-yet-unexplained occurrence of time travel.
In 1977, our heroes' troubled leader, Jack Shephard (Matthew Fox), convinces his friends that detonating a hydrogen bomb at the Swan Station (or "the Hatch," as it was known in Season 1) will prevent the discharge of energy that caused Oceanic 815 to crash on the island in 2004. The idea is the plane would land safely at LAX, and the castaways would get a second chance at normal lives.
Jack drops the bomb into the Swan excavation site where the DHARMA Initiative science team has drilled into a pocket of electromagnetic energy. The bomb doesn't go off. Magnetism begins to pull all surrounding metal into the drill site, and fertility doctor Juliet (Elizabeth Mitchell) is caught up in heavy chains and pulled toward the well. Reformed con man Sawyer (Josh Holloway) attempts to save her, but Juliet lets go, falling to her doom.
In 2007, a strangely confident John Locke (Terry O'Quinn) has seemingly risen from the dead, and is giving orders to the former leader of the island's natives, Benjamin Linus (Michael Emerson). Locke demands he be taken to see Jacob (Mark Pellegrino), the mysterious keeper of the island whom no one, not even Ben, has ever seen. Locke plans to force Ben to kill Jacob.
In a flashback to the 1800s, we see Jacob and an unidentified man in black (Titus Welliver) talking on the beach. The MIB tells Jacob that he wants to kill him, but that he can't do so until he finds a "loophole." Further flashbacks show Jacob visiting Locke, Jack and other castaways before they crash-landed on the island.
As they wait outside Jacob's dwelling in 2007, Sun-Hwa Kwon (Yunjin Kim) and other castaways are shown something found in the cargo hold of the plane they flew back to the island - it's Locke's lifeless body. "If this is Locke, then who's in there?," Sun asks.
The man we presumed was Locke approaches Jacob, who says, "Well you found your loophole." Ben confronts Jacob, demanding answers. Jacob offers none, and Ben stabs him. As the faux-Locke kicks Jacob into a fire pit, the dying man whispers, "They're coming."
The story shifts back to 1977, where Juliet has survived her tumble down the well. She finds the H-bomb still intact and bashes it with a rock. The screen goes white. Season 5 ends.
What we know
Tread carefully, fans, we're about to venture into spoiler territory.
The things we know for certain about Season 6 concern the cast. Many actors whose characters have been presumed dead will return in some way for the final season. Among them: Rebecca Mader (Charlotte), Dominic Monaghan (Charlie), Harold Perrineau (Michael), Ian Somerhalder (Boone), Cynthia Watros (Libby) and even "Heroes" co-star Greg Grunberg, who played the pilot of Oceanic 815 in the show's first episode.
Three prominent characters from Season 5 join the regular cast this year: Nestor Carbonell (Richard Alpert), Jeff Fahey (Frank Lapidus) and Zuleikha Robinson (Ilana). Also back is original cast member Emilie de Ravin as Claire, who hasn't been seen since Season 4 when she was hanging out in Jacob's cabin with her dead (?) father, Christian Shephard.
Gone from the regular cast this year is Henry Ian Cusick, but E! Online's Kristin dos Santos reports he will return as the time-skipping Desmond Hume in a guest role.
What we want
Here are five questions "Lost" needs to answer for its audience:
• Did the bomb prevent Oceanic 815 from crashing? The return of several cast members suggests that it did. But doesn't that negate the last five years of storytelling?
• Who is the man in black, and why did he want to kill Jacob? We can infer that the MIB assumed the identity of John Locke once his body was brought back to the island. Is it possible that all the dead people we've seen on the island have been the MIB in disguise?
• What do the numbers mean? Hurley used them to win the lottery. They were the code for the Hatch's computer. And in one Season 5 episode, it sounded like Hurley was repeating them over and over again on a transmission picked up by a French science team. Will we ever understand the significance of 4, 8, 15, 16, 23 and 42?
• Who are "Adam and Eve"? Way back in Season 1, Jack and Kate discovered two skeletons in the caves near the beach. Were they seeing themselves?
• Will Locke find redemption? He emerged as the main character in the last season, and his path from being crippled and alone to assuming leadership of The Others has forged the show's most tragic tale. Could it really be all over for the island's man of faith?
The answers are coming. Set the DVR and get ready for the last hurrah of a pop culture phenomenon.
Who's really 'Lost' forever?
• Boone Carlyle (Ian Somerhalder) - Succumbed to wounds suffered after the small aircraft he was in plunged off a cliff
• Dr. Leslie Arzt (Daniel Roebuck) - Blown to bits by old sticks of dynamite while explaining to Jack and Co. why he was the only one qualified to carry them
• Shannon Rutherford (Maggie Grace) - Shot by Ana-Lucia Cortez, who mistook her for one of The Others
• Ana-Lucia Cortez (Michelle Rodriguez) - Shot by Michael Dawson, who was told by The Others to release Benjamin Linus from the Hatch in exchange for his son, Walt
• Libby Smith (Cynthia Watros) - Shot by Michael after she witnessed the killing of Ana-Lucia
• Mr. Eko (Adewale Akinnouye-Agbaje) - Slammed to the ground by the Smoke Monster
• Nikki and Paulo (Carol Stream native Kiele Sanchez and Rodrigo Santoro) - Critically and publicly reviled, these short-lived characters were buried alive after being paralyzed by spider bites
• Charlie Pace (Dominic Monaghan) - Drowned in an underwater DHARMA station shortly after warning Desmond Hume about the freighter off the island's shore
• Danielle Rousseau (Mira Furlan) - Shot by Charles Widmore's mercenaries from the freighter
• Alex Linus (Tania Raymonde) - Shot by mercenary Martin Keamy after her dad's attempt at reverse psychology failed miserably
• Michael Dawson (Harold Perrineau) - Killed in the freighter explosion as the Oceanic Six watched from a helicopter
• Charlotte Lewis (Rebecca Mader) - Succumbed to sickness brought on by time travel
• John Locke (Terry O'Quinn) - Strangled with a cord by Benjamin Linus just minutes after Ben talked John out of hanging himself
• Daniel Faraday (Jeremy Davies) - Thanks to time travel, he was shot by his mother, Ellie Hawking, months before he would even be born
• Jacob (Mark Pellegrino) - Presumed dead after he was stabbed by Benjamin Linus, then kicked into a fire by John Locke's impostor
• Juliet Burke (Elizabeth Mitchell) - Presumed dead after pounding on a nuclear device with a rock
The Associated Press contributed to this report.