Lost, overseen by executive producers Damon Lindelof and Carlton Cuse, ended its run Sunday night with a divisive finale. Even minutes after the episode ended, a viewer’s cursory survey of the web showed the two camps: there are those who fell in love with a symbolic ending rooted in a religious mysticism and fully accepted the lack of answers, and those who felt that the ending wasn’t the proper culmination of six seasons of smoke monsters and glowing lights in caves.

The show didn’t so much answer the long-dangling mysteries as it did ignore them altogether.

When the ABC show began in 2004, it was ostensibly about the survivors of the crash of Oceanic Flight 815, a Sydney to Los Angeles flight that carried a diverse group of strangers who would come to know one another all too well over the 100-plus days that followed. Crashing onto a (seemingly) deserted island, they encounter a place that’s far from mundane.

• Jaimie Etkin: The Weirdest Lost Fan TributesWhat they found was a magical place where miracles take root: where a paralyzed man can walk again, a terminally ill woman can be healed, where all of them can learn to let go of their previous lives. The last element was delivered to the audience through the show’s trademark flashbacks, a narrative device that allowed the writers to explore the characters’ backstories off of the island. Later, some of the characters escaped, but opted to go back to save the others, beginning again the never-ending cycle of good and evil that punctuates the lush landscape of this impossible place.

Season 6, this last season, introduced a new conceit to Lost’s already complicated mythology—and here is where we will both say “spoiler alert” and offer apologies to those readers who have not watched the show—it is not easy to explain.

The final season of Lost presented an alternate—or Sideways—universe where the characters didn’t crash on the island and had lives that were in some cases very different from what we thought we knew about them. Guilt-ridden doctor Jack Shephard (Matthew Fox), for instance—suffering from some severe daddy problems and a major God complex—had a son in this Sideways world and was able to work out his own issues. Con man Sawyer (Josh Holloway) was a cop, though he was still out for justice for the man who caused his parents’ death.

With tonight’s two-and-half hour series finale, entitled “The End,” the audience finally learned just how this Sideways world connected to the larger narrative that had unfolded on the island, a series of plot twists that over the years has included time travel, flashbacks, flash-forwards, and a host of supernatural phenomena that poses some serious mysteries that have lingered over the show.

And this answer is what is causing the fan polarity: Because in the Sideways world, we learned in the final minutes of the finale, all of the characters are dead. The Sideways reality, a place where the Losties were able to let go of their traumas and connected with their loved ones, wasn’t really a timeline at all, but a purgatory that they themselves had created in order to find one another again, to reconnect one last time with the most important people in their lives before they could move on to the afterlife.

“The End” didn’t so much answer the long-dangling mysteries—Why do pregnant women die on the island? Why was the character of Walt (Malcolm David Kelley) special? What is this island? What was with all of the Egyptian hieroglyphics? What was the character of Desmond’s ultimate purpose on the island?—as it did ignore them altogether.

It focused instead on providing an ending for the island-based characters and offering a coda to the show that placed it in the realm of the spiritual rather than the mundane.

Here’s another thing people who’ve followed the show closely in the hope that all will be explained are going to be mad at: At the very beginning of Lost, one of the most popular viewer theories about the show was that the island was a purgatory of sorts, a place between life and death that the passengers of Oceanic Flight 815 had found themselves after dying. It seemed to explain a lot of the inexplicable, between the appearance of ghosts and horses, polar bears and smoke monsters. But Lindelof and Cuse maintained that that wasn’t what the island was.

Which is true. Sort of.

Here’s what we know. While the island is meant to be a real place, it’s also a battlefield for the forces of good and evil, between those who would sacrifice their lives to protect a mystical energy called The Source—a glimmer of which exists within all of us—and those who would use it for their own corrupt ends. The mysteries that life on the island have kicked up have entranced and intrigued viewers for six years.

But then there was that Sideways world that we’ve watched this season, a place where the castaways were still connected by invisible threads of fate, a web of interconnectedness that seemed to grow tighter as the season wore on. Just what did it mean? Clearly, the relationship between the island and the Sideways world was going to explain everything.

In the finale, in the Sideways timeline, Desmond had gathered together the passengers of Oceanic Flight 815 and “awakened” their dormant memories of their lives on the island, bringing them all together at a church for some of the final moments of the episode, and the series. Along the way, former lovers reunited in a series of beautiful, moving vignettes that captured their shared experiences on the island and the bonds of love that even death can’t break.

It’s that last fact that’s vital, for each of these characters was dead, this world nothing more than a self-created purgatory designed to bring them together one last time, to accept their deaths, and move on, letting go of all of it. At the church, it was a funeral they were throwing for themselves, before the doors opened up and white light washed over all of them. It appeared to be quite—heavenly.

While that’s a feel-good ending, it’s also an easy way out. While Cuse and Lindelof denied the purgatory aspect of the island years ago, it turned out to be the ultimate solution here, presented in a context that’s meant to be universal: we all die.

For some viewers, that’s the ending that they wanted: a sense of resolution and finality (the ultimate kind, really), but others are likely to be frustrated by the lack of answers here, not just about the island but about this purgatory as well.

Because even in purgatory, there are questions of logic. Why weren’t Walt and Michael (Harold Perrineau) there? Why did we see the island at the bottom of the sea in the Sideways timeline? Why was Eloise Hawking ( Fionnula Flanagan) so adamant that Desmond (Henry Ian Cusick) not wake them up? How did she know that they were in an intermediate state?

Considering how much time viewers have spent trying to figure out the relationship between the island timeline and the Sideways one, it is also frustrating that it turned out that there is none—or more precisely, that what happened in the Sideways timeline didn’t affect what happened on the island at all. Desmond’s efforts to awaken the castaways in this purgatory, for example, didn’t lead them to rise up to defeat the evil Man in Black or save the island. Because of that, the show could have just ended with Jack dying in the bamboo forest where this all began, fulfilling that journey of human condition: from awareness and life to closing one’s eyes and diving into the big sleep.

However you felt about the actual final ending—or more precisely those last 10 minutes in the church—the majority of the episode, particularly the highly cinematic and taut sequences set on the island was magnificent. For Jack, Kate (Evangeline Lilly), Sawyer, and the others, it was a time of monumental change, of sacrifices made, escapes taken, a final flight that didn’t crash but soared away from a place of mystery.

Left behind and aboard that plane winging into the blue sky were the characters that we’ve come to know and love over a journey that has lasted six years. If the series finale of Lost achieved anything, it’s that it proved in no uncertain terms that we still care deeply about these characters. Like them, however, our journey is now done and we too must learn to let go.

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Jace Lacob is the writer/editor of Televisionary, a website devoted to television news, criticism, and interviews. Jace resides in Los Angeles. He is a contributor to several entertainment Web sites and can be found on Twitter and Facebook.