The Deep Blue Sea, the second feature and first work of fiction directed by Terence Davies in the last twelve years, is based on a play from 1952 by the legendary British writer Terence Rattigan, and was adapted by Davies as his contribution to a centenary celebration of the late author's work; but it never, ever feels that way. This was the first and most superficial of the thoughts that came to me while watching the movie: it is so breathlessly alive as a work of cinema that, while the shape of its theatrical form may still be barely visible (I have neither read nor seen the play), the film presents its story in a way that is unimaginable in any other medium, and it fits so smoothly into Davies's career-long fascinations with post-WWII England and the expression of feminine will in a chauvinistic setting, it's easy to believe that it was his story all along.

But no, this is ultimately Rattigan's scenario, however much Davies makes it his own thing, and that is not something to glide over. For one thing, it answers the most curious flaw of the movie, which its distinct lack of timelessness; there is so much weight given, both in the narrative and as a thematic idea, to Britain After the War, that it never quite gets around to feeling like it has much of anything to say as a film produced in 2011, though given the incredible importance of nostalgia in Davies's cinema, paired with a certain reactionary streak (explored almost to the point of comic absurdity in his 2008 docu-memoir Of Time and the City), makes it easy to believe that this has more do to with the screenwriter-director's interests than with any particular limitation of Rattigan's text. It is, after all, quite a robust and heady little character drama, and while the specifics are uniquely tied to an era - "about 1950", in the dry phrasing of an opening title - the emotions are not.

The Deep Blue Sea is the story of Lady Hester Collyer (Rachel Weisz), the wife of Sir William Collyer (Simon Russell Beale), who has for some time been having an affair with a veteran named Freddie Page (Tom Hiddleston). When we enter the picture, she has been driven to attempt suicide in the grubby apartment where she and Freddie have been living for some time; from this vantage point, we follow along with her recollections of how she and he first met up, what it was about her marriage to William that sent her into the arms of another man, and - this being the really crucial part - the slow process by which she discovered that her love for Freddie was all out of proportion to his love for her, which could be more accurately described as a vivacious sexual infatuation, paling next the enormous feelings she harbors.

The title, derived from "between the devil and the deep blue sea", refers to Hester's awful stuck position between comfortable, blank amiability from her husband and all-consuming, exhilarating but destructive lust from her lover; the scenario sets up an unwinnable situation for her in which nothing at all works, and the position she arrives at by the film's end counts, at best, as the most tolerable of several dreary possibilities. Davies frames this story in a pair of tracking shots that mirror each other - the film opens by moving over to a building and up to a window, and ends by moving down from the window and away from the building - and the very first and very last image we see is off the rubble of a building destroyed in the Blitz and not restored; rather obviously, he's equating Hester with a post-war England that no longer got to be a world power and had to find some way to to rebuild itself into the best country possible out of what was left. It is a guardedly optimistic metaphor - the opening shot is dark, so we can only see the rubble, but the final shot is during the day and we can see the proud, old buildings of London rising out of the wrack - and a metaphor that Davies pushes a bit too eagerly, and if there is one reason why The Deep Blue Sea doesn't work quite as well as his luminous autobiographical study of post-war life, Distant Voices, Still Lives, it is at least partially because it is so leading.

The good news, then, is that Rattigan's play provides such a bombshell of a role describing a woman in considerable turmoil - Peggy Ashcroft, who created the part onstage, was supposedly quite worn down by the intensity of it - that Davies is obliged to follow along; and I should concede immediately that The Deep Blue Sea is undoubtedly first and above all about Hester's emotions and need for happiness, and whatever misgivings I have about the 60-year-old political metaphor are chiefly because this is both the movie's only serious flaw, and the only thing to distract us from a stupendous performance by Rachel Weisz, one of those actresses that I, personally, always like, though frequently the difference between Weisz fan and Weisz apologist is rather thinner than we fans might like. No apologies are necessary here: this is a great performance, almost undoubtedly her best work. It is a scorching performance that trumps my ability to talk about it, really: she is aided by good supporting turns in the form of Beale (nine years her senior) and Hiddleston (eleven years her junior), and Ann Mitchell as a quiet, observant landlady, all of which force her into different registers of passion, defensiveness, and reaction; and aided, too, by a director who allows the movie to stop dead in its tracks as a narrative to follow the subtleties of her physical performance, given that Hester and not the narrative is the thrust of the movie.

Indeed, what is most impressive about the film beyond Weisz is almost entirely a matter of how Davies shapes the whole thing around the actress and the character, binding us to her chronologically fragmented perception - the opening scene, a series of flashbacks accompanying Hester's suicide attempt, structured in fading moments that resemble someone's attempt to pay attention while falling asleep, all as Samuel Barber's Violin Concerto, Op. 14 roars in the aural foreground, is a nearly perfect short film, focusing on the mind of a woman at a moment of decision in an poetic, impressionistic manner that manages to completely avoid feeling abstract - and using bleary, drab cinematography to sharply define Hester, wearing the only heavily-saturated colors in the film and frequently a half-stop lighter than the rest of the frame; not in opposition to the world around her, but simply to present her as a discordant element.

It is a quiet, stretched-out film about intense feeling, and Davies does not always avoid the obvious way of depicting this (hence the color thing); but there is a scrupulousness to the visuals in the film that end up mattering more than being less-obvious would. Besides, this is not, like Distant Voices or The Long Day Closes, a directorial showcase; it is a showcase for a performance, and the director is largely focused on making the best possible environment for that performance to absolutely devastate us. And this is what it did, for me anyway; I shall not say that I think it's impossible I'll see a more perfect piece of cinema acting in the rest of 2012, but I will say that if I do, then 2012 will be one hell of a year for movie acting.