Here is a determinedly old-fashioned drama, verbose and elaborate but also forthright and watchable in its way. It is a Stoppardian what-if meeting, imagining a bruising encounter between two celebrated historical figures who could, theoretically, have run into each other; it is adapted by director Matt Brown from a stage-play by American dramatist Mark St Germain, in turn inspired by a 2002 book by Harvard psychiatrist Armand Nicholi who had seized upon a report that Sigmund Freud met with an unnamed Oxford don just before his death. What if that don was CS Lewis, the Christian apologist who in his 1933 book The Pilgrim’s Regress had mocked atheist Freudianism and every other sort of godless trendiness?

Anthony Hopkins plays Freud at the very end of his life in exile in London in 1939 as war breaks out, in agony from mouth cancer. Matthew Goode is Lewis (also once famously played by Hopkins himself, of course, in the film Shadowlands), for whom fame through the wartime broadcasts and Narnia bestsellers was still in the future. Hopkins’ Freud is querulous, cantankerous and bad-tempered; Goode’s Lewis is diffident and supercilious. Lewis says Freud’s worldview is morally evasive; Freud smirkingly suggests that Lewis’s emotional relationship with the mother of his fallen first world war comrade is classic neurosis.

There is no great meeting of minds here, and in fact the drama would be insufferable were it not triangulated by the figure of Anna Freud (sharply played by Liv Lisa Fries), bullied and oppressed by her father, frantically running through the rain to deliver the medicine he has demanded quite unaware that the selfish old brute had quite forgotten he had asked for it. Not a terribly profound movie, perhaps, but robustly performed and an interesting reminder of the dusty old debates on the point of being swept away by the great horror of the second world war.

• Freud’s Last Session is in UK cinemas from 14 June.