Lost, which ended 10 years ago tomorrow (23 May), has the most misunderstood finale of all time.

Upon its initial broadcast, the divisive two-parter caused a large number of disappointed to incorrectly think: “Oh, so they were dead all along.”

Fortunately, we’re on hand to debrief you on what actually happened in that final scene so that the next time someone makes the above statement – most probably after working their way through the series on Amazon Prime – you can roll your eyes and direct them to this (as well as this new oral history of the show featuring words from Damon Lindelof, Evangeline Lilly and Jorge Garcia).

BEWARE – major spoilers for the ending of LOST follows.

The final ever scenes of Lost are intercut between events on the island and an alternate timeline known as the flashsideways – scenes that replace the flashbacks and flashforwards for the entire final season.

These flashsideways scenes come after Juliet (Elizabeth Mitchell), stuck in the 1970s, detonates a hydrogen bomb in the closing moments of season five in an attempt to prevent the hatch from ever being built. The logic is that, should the hatch never be created, Oceanic Flight 815 will never crash on the island. The flashsideways show what would have happened had the plane landed safely in Los Angeles.

All season long, viewers see the characters rubbing shoulders with one another in Los Angeles, unaware of the events of the past five seasons.

Eventually, these characters are drawn together and begin to recall their time on the island, which leads to the final scene’s revelation: they are actually dead in the flashsideways, which is essentially a netherworld the survivors created in order to congregate so they can move on together to “whatever comes next”.

So, to clear up the confusion: in the flashsideways scenes, these characters are dead. But no, they were not dead all along after the plane crashed.

The flashsideways scenes depict an afterlife that the characters constructed for themselves due to the fact that their time on the island – which was completely real from start to end – was the most important part of their respective lives.

The characters present in that final church scene are characters both dead and alive in island time, meaning several characters (including Kate, Sawyer and Claire) went on to live a full life beyond the series finale.

These flashsideways scenes present a purgatory-of-sorts, where these characters come to when they eventually do die whenever that may be. When broken down, it’s a beautiful and reassuring depiction of the afterlife.

The plane crash, the smoke monster, the hatch, the island – it was all real.

Of course, it almost all ended rather differently...