All you need to know about this episode is that it is a Desmond episode.

That very knowledge, as a fan of ‘Lost’ (and let’s be honest, if you’re still watching the series – and I certainly think it has maintained a high enough quality that you should be – you’re dedicated to the mythology and characters) should be enough for you to expect two things.

First, the episode will be a major milestone in the series’ storyline. Think about it: what Desmond-centric episodes have been unessential?

• ‘Live Together or Die Alone’ – not only a great introduction to the character (and let’s be upfront about this: Henry Ian Cusick is one of the best actors in the series), we also learn what happens when you don’t press the button in the Hatch- and that Desmond crashed Oceanic Flight 815. Oops.

• ‘Flashes Before Your Eyes’ – At the time, I thought this episode was an anomaly. Desmond hallucinates that he’s traveled back in time, and who is that creepy jewelry store lady who keeps telling him that he can’t change history? Go back and re-watch this episode, and you’ll see what a tectonic-shifting episode this really was in the series’ mythos.

• ‘The Constant’ – Seriously, if you need to ask why this episode is pivotal, then hand in you ‘Lost’ fan card and go sit over by the ‘Hannah Montana’ crowd.

The second thing to expect in a Desmond-centric story is a solid performance by Cusick. He is the most consistent actor in the series, able to dynamically convey despair, anger, and love that you are absolutely drawn in to the story. And if the star-crossed Desmond-Penny relationship has failed to move you even a little, then you have no soul.

After so much hype, is ‘Happily Ever After’ really that good?

Yes. ‘Happily Ever After’ begins to give us the bigger picture of how the parallel universe fits into the narrative.

Smartly, the episode is structured similar to ‘Ab Aeterno’, in which most of the episode is comprised of the (in this case) flash sideways.

Continuing the trend we have seen this season regarding the parallel universe, Desmond’s life is (at first) seemingly better; he is a successful business man who has a close relationship with Widmore. When a plot contrivance forces Desmond to babysit Charlie, Desmond begins to understand that something is wrong with the world around him, and this leads him to make some critical choices by the end of the episode.

‘Happily Ever After’ works best due to its multi-layered approach. The inverted relationship Desmond has with Widmore, the parallels of Desmond taking care of Charlie in this universe to the Desmond/Charlie relationship in the main universe, to how alt-Desmond first meets alt-Penny (echoing Desmond and Jack’s first fateful meeting); these are all elements that make this episode a real treat for long-time viewers.

These are not just mere nods to the audience; these are deconstructions of the overall mythology and our expectations of these characters.  For the dedicated viewer, it is fascinating to watch.

There are a few reservations about the episode, all pretty minor. The chase scene through the hospital, thankfully short-lived, was painfully cliched. Desmond appeared to agree to go with Sayid a little too quickly and easily; and speaking of Sayid, for a man who is supposedly filled with darkness now and ruthlessly killed Dogen and his interpreter, he seems pretty merciful to Widmore’s people in kidnapping Desmond.

In all, an important episode to watch, with a well-written script and a reliable Cusick at the center.

Next week: Dude… trust Hugo…