I'm always fascinated by the phenomenon whereby an entertainment property or piece of art takes on (or is ascribed with) more subtext or deeper philosophical meaning if it's popular enough to survive or thrive for decades. We see it with Batman, today a Grand Guignol metaphor for whatever political or social themes you care to mention depending on your era but which was originally conceived as a kind of silly story for kids.

I'm finding a lot of these old classics carry a lot of weight because of the amount of love around about them, and when I finally watch them I'm surprised by how shallow they are compared to what I was expecting. I guess in a lot of cases the sparkling, witty dialogue of the screwball romantic comedy era is enough to engender that love in a lot of fans.

Like a lot of other films of the postwar years (The Big Sleep is another example I finally watched not long before writing this review), The Apartment is very theatrical. That is, there are no special effects or expansive outdoor shots, it's just people talking in a few locations on 40s or 50s-era studio backlots or a few tightly controlled exteriors with nothing to carry you along apart from dialogue and plot.

In this case it's about the slightly sad sack C C Baxter (Jack Lemmon), a working schmoe whose colleagues rely on him to vacate his Manhattan bachelor pad at the most inopportune times for their romantic trysts. All while he puts up with being thrown out for hours on end at any hour no matter what the weather (and coming home to a place strewn with mess and all his booze gone), Baxter pines for the perky, kewpie doll-like Fran Kubelik (Shirley MacLaine, as young as you've ever seen her), an elevator operator in his gigantic faceless insurance corporation employer's building.

In return for facilitating their extramarital love lives, Baxter's immediate managers talk him up to the big, big boss, Sheldrake (Fred MacMurray). Sheldrake initially seems only impressed with Baxter's performance, but when he promotes him it's obvious he has an ulterior motive, asking Baxter to give up his apartment that very night for Sheldrake's own sexual liaison.

He offers Baxter two tickets to a show to help sweeten the pot, so Baxter figures it's the perfect opportunity to ask Fran out. She gratefully accepts, telling him she only has to fulfil a quick prior commitment before she joins him. The prior commitment, we soon learn, is to confront Sheldrake about their relationship and how it's going nowhere.

Sheldrake promises he's going to leave his wife, his sweet talk convincing her to accompany him to Baxter's apartment, none of them except Sheldrake himself aware of the connection, while Baxter himself waits all night outside the theatre for her.

Stood up and depressed, he eventually goes to a bar and picks up a bimbo, taking her home where – to his horror – Fran is unconscious in his bed. After feeling wretched for believing Sheldrake's lies once again when he leaves her at Baxter's apartment to return home to his family, Fran has taken a handful of sleeping pills and gone to bed.

Having rudely sobered up and ushered the bimbo out, a frantic Baxter drags his doctor neighbour in to hep Fran and they gradually bring her round. Maudlin at the wreck her life's become, Fran refuses to eat or even get out of bed while Baxter lovingly tends to her, finally having the woman he wants in his presence.

But the Wilderesque romantic entanglements haven't finished with Baxter or Fran yet, and the fallout from Sheldrake's indiscreet romantic past soon threatens heartbreak on all sides. With the temptation of another huge promotion dangled in front of Baxter and more empty lies from the man she thinks she wants dangled in front of Fran, will they be able to follow their hearts instead?

The subject of a suicide attempt has a very different connotation today – back then it didn't seem to have a lot of dramatic weight beyond a plot device, but it'd be interesting to ask the late Billy Wilder how dark he intended for it to be. It doesn't jar in what's essentially a romantic comedy of errors as much as you think it will simply because it's treated almost as comically as any other plot turn in the movie.

But whatever metaphor you want to look for after all these years, Wilder is on full form, doing what Woody Allen would make a career out of decades prior and doing it with as much comic sparkle, sweeping Mancini-esque (actually done by a composer called Adolph Deutsch) score and jaunty, witty dialogue as you hope for from the genre in this distinctive era.