I know we’re 2 years behind, but we finally watched all 90-100 hours of LOST and I can now offer up this ‘grand unified theory’ to explain the 6-season story. (It’s high-concept modern myth-making; the only other recent show to have done this well is BSG.)

Synopsis: 2,000 years ago, Jacob unwittingly unleashes the Devil (‘Smokey’) upon the Island, which is the physical manifestation of Hell on earth. While Smokey seeks to escape the Island and wreak havoc upon the world, Jacob’s plan is to bring a series of ‘half-damned souls’ to the Island in the hope that they can redeem themselves and each other to somehow defeat Smokey. Even though Smokey finds a way to murder Jacob, his final set of ‘candidates’ – the survivors of Oceanic flight 815 – eventually discover their purpose and succeed at their task at great self-sacrificial cost, and are rewarded by reuniting as eternal friends in the after-life

More details:

THE ISLAND: is the physical manifestation of Hell on earth: it is a protective bubble around the Source, which is mystical energy that acts like space/time-traveling ‘electromagnetism’. Generally only ‘damned’ souls make it to the Island, and they are tortured by being made to relive the most regrettable moments of their lives (the ‘flashbacks’, which could also be time travel flashes back to those moments.) Those who die on the Island while stlil damned are trapped and become the ‘whispers’ (e.g. Michael). Also, two damned souls can’t birth a baby on the Island.

SMOKEY: a malevolent entity that escaped from the Source when Jacob killed his brother and threw him in there, and is constantly seeking both to murder Jacob and leave the Island. Smokey can only take on the form and memories of the dead (when not in Smoke Monster form), e.g. when he was first released, as Jacob’s brother, and during seasons 5-6, John Locke, with many others in between (e.g. Jack’s father, Eko’s brother, etc.) While the Source remains plugged, Smokey is immortal but is trapped on the Island, and it is somehow not permitted to directly kill the Island’s Protector or his/her ‘candidates’. When the Source is unplugged by Desmond, the Island starts to collapse and Smokey can escape, but it also becomes mortal.

THE PROTECTOR: person who is currently charged with protecting the Island, until he/she can find a successor. The Protector stops ageing, but can be killed normally (just not directly by Smokey), which is the only way to release them from their duty. Jacob has been the Protector for 2,000 years, followed by Jack for 1 day during the series finale, then Hurley ‘for a long time’.

THE OTHERS: people brought to the Island over the ages by Jacob as part of his plan to find a way to defeat Smokey, and defend the Island against any other threat. Jacob believes in free will and takes a ‘hands off’ approach in guiding them (so they frequently do not act benevolently e.g. kidnapping Walt), plus for his own safety he established a procedure where his secret hideout could only be visited occasionally by the Leader of the Others together with Richard. Since the 1970s, the Leaders have been, in order: Charles Widmore, Ben Linus (those two are mortal enemies), John Locke, and Smokey (as ‘fake Locke’)

DHARMA INITIATIVE: scientists who discovered the Island in the 1970s and who seek to explore and exploit its special ‘electromagnetic’ properties. However in so doing, they unknowingly risk disrupting the Source, destroying the Island and unleashing Smokey (hence the Others violently oppose them). They also figured out Smokey could be kept at bay by a wall of sonar towers