This review may contain spoilers.

I didnt think it was possible. I thought the best episodes of Lost were already neatly packaged in DVD box sets, while current viewers would be fed a steady stream of satisfying, even solid episodes while the creative team wrapped up the loose ends. Ab Aeterno proved me wrong. It was, in my view the best episode of the series.

This episode possessed all of the elements that made us love Lost in the first place. Using its classic flashback technique, viewers get to plumb the background of what has been, so far, a relatively minor character: Richard Alpert (Nestor Carbonell). Along the way, viewers are fed a healthy dose of the shows mythology, this time providing answers instead of more questions.

Carbonell delivered a stunning, Emmy worthy performance which showed the depths that he had gone in order to become immortal. His grief seemed genuine, his fear was real, and the tortured soul that he had become finally made sense. Its amazing that the writers squandered this immense talent for so long. I was never much of a Richard Alpert fan, and I had no idea that Carbonell was this good of an actor. Much like Zachary Quintos performances of Sylar on Heroes, Carbonell seemed to be way too good to be housed as a minor character on a television series. He simply outshined everyone.

This final season has had its high and low points, delivering some of the best episodes of the series intermingled with a few disappointing efforts. None of the episodes has been able to do what Ab Aeterno did: capture the feeling of the first season of Lost while delivering a new, meaningful story. In short, it was a masterpiece.

What Worked

Now we know how the statue was broken. That was an excellent scene, almost worthy of a motion picture.

The whole story of Richard Alpert, his dying wife, and his meeting up with Jacob was the best executed back story of any episode of Lost. It makes all of the Kate (Evangaline Lily) love triangles seem trite and silly, which of course, they are.

Jack (Matthew Fox) finally learns that Locke (Terry OQuinn), or at least a monster impersonating him, is on the island.

Titus Welliver delivers a solid performance as the Man in Black. The episode was very unsettling with all of its references to Hell.

Loved the title: Ab Aeterno, which in translation means since the beginning of time.

What Didnt Work

The commercial breaks.

Giving Credit Where Credit Is Due

Lost stars Matthew Fox, Evangeline Lilly, Terry OQuinn, Josh Holloway, Jorge Garcia, and Michael Emerson. Ab Aeterno was written by Melinda Hsu and Greggory Nations. It was directed by Tucker Gates.

Lost airs Tuesdays at 9 p.m. ET on ABC.