For the second time in 26 years, Twin Peaks has ended. But after last night's two-part finale quickly resolved the fate of Dale Cooper's evil doppelgänger, it proceeded to literally open up a whole new world of mystery. Anyone looking for a neat resolution to the myriad puzzles of David Lynch and Mark Frost's spellbinding series will likely feel a little lost right now.

When Showtime president and CEO, David Nevins, described Twin Peaks: The Return as the 'pure heroin vision of David Lynch', he really wasn't kidding. Over 18 extraordinary hours, Twin Peaks has steadfastly carved its own path, confusing and confounding at every turn. Episode eight ostensibly served as an origin story for BOB, the evil force that infected residents of Twin Peaks, and it did so by journeying into the heart of an exploding atomic bomb. Much of that episode was wordless and Lynch's mastery of sound has been crucial to the show's success, although, as an artist, Lynch is constantly aware that he's working in a predominantly visual medium, and so the imagery throughout The Return has been some of the most extraordinary ever seen on TV.

In 1990–91, the original two series redefined modern television, paving the way for the medium's golden age. And so it was never likely that Lynch and Frost would come up with anything as simple as a nostalgic rerun. Instead, The Return was unlike anything else on TV. Presented as an 18-hour film broken into weekly pieces, it was funny, daring, confusing, irritating and frightening – attributes that could equally apply to the original series (certainly season two). What other show would nullify its popular hero for almost the entire run? And what other show would recast the late David Bowie as a huge steaming kettle?

Lynch has often spoken about his fondness of mysteries, and The Return had intrigue in spades, slowly drip feeding its secrets over 105 days. Fan theories have abounded and, every time it seemed we had it sussed, Lynch and Frost would gleefully pull the rug from under our feet. Twin Peaks now has a vastly more elaborate mythology which will invite much discussion over the coming years. It has also created new layers of intrigue over the original series and feature film, Fire Walk With Me, thanks to the penultimate episode's extraordinary use of previously unseen footage.

In 1991 we were left with the image of a bloodied Cooper maniacally repeating, 'How's Annie?' (a question The Return failed to address at all, let alone answer). And now we've been left with Cooper (or is it Richard?) asking Laura (Carrie?), 'What year is this?' before she let out a blood-curdling scream. So many questions remain unanswered: where is Audrey? Who was the young girl in episode eight? What is happening with Sarah Palmer? The impact of these new revelations will be debated long into the future, and if we really have reached the end of the road then we'll be swimming in a sea of speculation forever more. Here's hoping we don't have to wait another 26 years for more answers.