THE THIRD MAN (Cert. U) is back in cinemas in a sparkling digital restoration. Black-and-white film’s numinous contrasts of luminosity and darkness create an almost theological antithesis — especially with an original screenplay by Graham Greene, Robert Krasker’s iconic lighting, and Carol Reed’s masterly direction. Where is God, or at least goodness, to be found? In the light, or there among the shadows?

The Third Man won the 1949 Cannes Film Festival’s Grand Prix, becoming one of cinema’s most appreciated movies. Racketeers vie with military authorities striving to wreak order out of chaos. Holly Martins (Joseph Cotten) arrives in post-war Vienna to learn that his childhood friend Harry Lime is dead, suspected of dispensing lethally contaminated penicillin to hospitals. A sceptical Martins tries to clear Lime’s name, but finds himself descending into a miasma (visually represented by Vienna’s sewers) of human weakness and wickedness.

Orson Welles plays Lime. It is no accident the film’s revival coincides with his centenary. Everyone knows Lime’s Ferris-wheel speech implying that Switzerland’s sole contribution to civilisation was the cuckoo clock, whereas the Borgias’ tyranny produced sublime artistic achievements. Very Greene, even though written by Welles. Within the darkness of human hearts there also lurks a divine imperative.

Greene’s preceding dialogue nails this even better. Lime looks at the crowd below them. Would you really feel any pity if any of those dots stopped moving for ever? Martins retorts that Lime used to believe in God. “I still do, old man.” Herein lies the heart of the matter, of the film. Is there a God of pity in the thick of Lime’s “suckers and mugs”? Or a transcendent deity indifferent to their fate?

Mercy and forgiveness are hard-won in this movie. And not always yet on offer. Hence the way the story ends. The Third Man remains vibrant with redemption, actual or potential, and if you can’t see it at the cinema, a DVD/Blu-Ray packed with fascinating extra material from Studio Canal has now been released.