Sam Mendes’ “Empire of Light” bathes the viewer in the warm glow of nostalgia even as its reminds us that the Technicolor past had its sharp edges.

It’s a tale of memories and emotions, which will have to do, as the story has the studied aimlessness of a dream, and an unfinished dream at that.

The nostalgia is for the ebbing grandeur of the cinema, exemplified by its title character, a grand old art deco movie house by the sea, in Margate on the southern English coast. Mendes (“1917,” “Road to Perdition,” and a couple of Bond films) waxes lyrical about the last years of celluloid cinema and the unifying experience of seeing epic, broad-appeal comedies, character studies and histories in the “Blues Brothers,””Being There” and “Chariots of Fire” very early 1980s.

But he doesn’t really have a coherent story that would give his movie a point.

Olivia Colman is Hilary, the “duty manager” (assistant manager) of The Empire, a regal picture palace built before “The War,” a tourist town theater which in its glory days, had a ballroom and cafe on the roof, and as many as four screens. Now it’s a faintly-seedy but still popular duplex destination for the locals who still queue up for “Stir Crazy” and each week’s new attraction.

Hilary is a sad, efficient loner, drifting through her duties, smiling just enough at the banter among the Empire’s large, friendly working class staff. We see her solitary life — meals alone, solo visits to a an old dance hall where she takes a whirl with strangers in between perfunctory summons to the cinema manager’s (Colin Firth) office for illicit sex, doctor visits which note her late 40s state, weight gains and the medication.

Hilary’s on Lithium. And whatever ails her, there’s no joy in this life. She doesn’t even watch the movies she sells tickets to, no matter how the elfish, poetic pedant of a projectionist (Toby Jones, of course) goes on about the experience, the “illusion of motion” which is “an illusion of life, so you don’t see the darkness.”

“This whole place is for people who want to escape.”

Then a new usher is brought on board. Stephen, played by Michael Ward of TV’s “Small Axe,” is young, handsome, an aspiring architect who failed to get into university and is staring at a stark future himself. If any of them seeing the impending death of their jobs and that “experience” of going to the movies, they don’t let on. Stephen’s limited future is compounded by the fact that he’s Black, and this is Margaret Thatcher’s Britain.

Stephen and Hilary start one of those circumscribed, fatalistic affairs that the theater and the movies so adore, a “Frankie & Johnny” romance between two lonely people, showing us triggered flashes of the disorder that limited her life and the ugly, skinhead racism that is his lot to face, something that she would have never recognized had they not found a connection.

“Empire of Light” is being advertised with trailers that romanticize the cinematic past and promise that, if we aren’t getting a nostalgic romp like the early Peter Sellers cinema-set comedy “Big Time Operators,” at least Mendes will treat us to something like “The Majestic,” a Jim Carrey drama that used the same, sentimentalized “good old days of the movies” as its backdrop.

Mendes invites us to dream along with him, of beach town life and its rhythms, rocksteady and ragga music, double-decker bus rides up the scenic coast, a romance in which she encourages him with “Don’t let them tell you what you can or cannot do,” and he tries to get her to lighten her mercurial moods by watching the movies she never takes the time to see.

“Honestly, anyone would think you worked in a bank!”

But dreaming along only takes this movie so far. The affair is secret. Then it isn’t. Hilary is a poetry fan. And? Stephen’s interested in learning the archaic technology and art of carbon arc celluloid movie projectors. There’s a “regional premiere” of “Chariots of Fire” that promises to be a Climactic Event, and a harbinger of The End. The movie is littered with such details and not-quite-but-close random episodes, and the picture’s meandering drift becomes wearing.

We keep waiting for that defining, lump-in-the-throat statement of what all this might mean, a sense of the cinema as a cultural touchstone, a communal magic lost in an age of streaming video, empty spectacle, comic book and horror movies which reach their narrow audiences, but not “the” audience.

And as I check my notes, hunting for some grand Toby-Jones-as-projectionist profundity, I’m sad to say it never comes.

Colman is brilliant, Ward brings a lovely wounded nobility to Stephen and the warm and cuddly Jones is set up to sum it all up. But Mendes will not or cannot take us there in this personal project that perhaps needed another person or two’s input, and loftier re-writing before the camera ever rolled.

Rating: R for sexual content, language and brief violence.

Cast: Olivia Colman, Michael Ward, Toby Jones and Colin Firth

Credits: Scripted and directed by Sam Mendes. A Searchlight release.

Running time: 1:58