The Main Event: Lost

IT STARTED with such a simple premise that it was almost inevitable Lost would become synonymous with the most baroque, teasing and sometimes infuriating storytelling in contemporary television.

A passenger flight from Sydney to Los Angeles crashes on a tropical island and, miraculously, many people survive. They don't know where they are, why they're still alive or how they're going to stay alive – especially since there's something nasty in the woods. Flashbacks let the lives of the characters before the crash trickle out in deliciously ironic fashion – freckled-face Kate was actually a criminal, the chubby comic relief was a lottery winner and psychiatric patient, and the taciturn, Messianic survivalist turns out to have been a wheelchair-using fantasist up until the moment he fell out of the sky.

Lost was the first series that wholeheartedly exploited the new digital environment. You could watch it on your laptop and freeze the frames where portentous clues appeared – a map, a series of hieroglyphs, a glimpsed book, names that were clearly anagrams – and quickly Google their significance.

It specialised in "Easter Eggs", a term imported from computer games: little "hidden" clues, such as seeing one character appear in the background of a scene about another character in their "pre-Crash" lives.

Online "alternative reality games" supplemented the series, and Lost inserted itself, almost virally, into other programmes. In the run-up to the final series we've seen adverts for Hurley's fast-food restaurant, snippets of Kate on America's Most Wanted and a teaser picture with the principal characters in the guise of Da Vinci's The Last Supper. It actively encouraged the viewer to play detective to its vast puzzle, and countless fan sites hosted discussion boards where the most abstruse theories and inconspicuous details could be dissected ad infinitum.

But was it a puzzle with any solution, or an endless riff on deferral? At times, the producers seemed to be actively twitting the most intense fans, slipping in sly references to their theories in order to debunk them. This, however, is the Last Season, where – supposedly – the Answers will be given. In a way, I hope not. Lost has been so creatively ambiguous, any firm ending ("Well, you see, the people of Atlantis, who worshipped a giant Red Herring, had created a nanovirus…") will seem not only bathetic, but ludicrous. Moreover, since its themes – fate versus free will, faith versus science, chaos versus synchronicity – elude the solution of philosophers and physicists, I have doubts that TV executives will crack those conundrums. Better to end like the original series of The Prisoner, in such a riot of madness that people will still watch it 30 years later, ensnared in its riddles, ruefully quoting TS Eliot – "We had the experience but missed the meaning".

Is it even possible to start to watch Lost, at this late stage? Well, to get the most from it, you could buy the DVDs of the first 47 hours this afternoon, phone in very sick on Monday and be ready for Friday. Or there's a fan favourite "55-second recap" from Episode 5.02, where the programme satirises its own fractal narrative. I'm pretty sceptical about synopses, but here goes my attempt.

The survivors learned that the Island used to be inhabited by a 1970s weird-science commune called The Dharma Initiative. Almost all of them had died in a conflict with the indigenous "Others": barefoot bedraggled pirates who whispered in the forest. It turned out the Others now lived in the Dharma bases, and only disguised themselves as primitives. In fact, they're sophisticated, chino-wearing psychopaths in charge of a vast organisation. They worship an unseen figure called Jacob, whose orders are enforced by Ben, a bug-eyed Machiavel. Rescue arrived – only it turned out to be another violent faction, led by a former leader of the Others whom Ben had usurped. The Island was moved in time and space just as a few "Losties" escaped. They were persuaded to return, but something went wrong, and they ended up in the 1970s as Dharma recruits, inadvertently instigating the very war that would wipe out the Initiative. To put time back in joint, some survivors tried to detonate a nuclear bomb in the past. Jacob, an aloof and humble man who had a connection to all the survivors, finally was revealed; as was his unnamed nemesis (referred to by fans as The Man in Black or Esau). Locke goaded Ben into killing Jacob, and Jacob hinted that "Locke" was Esau – a hypothesis strengthened when Locke's corpse was found. In the last seconds, the bomb went off. So too did all bets about what the heck was going on.

Confused? I think that's the point. I still want to know what was going on with the hair brushes – in Season One somebody commented that it was odd there were no hairbrushes in the luggage debris. It seemed so important at the time.

The final season of Lost begins on Sky One on Friday at 9pm. Stuart Kelly will host an online debate during that broadcast at www.scotlandonsunday.com

• This article was first published in Scotland on Sunday, January 31, 2010