If “Freud’s Last Session,” writer-director Matt Brown’s follow-up up to his 2015 effort “The Man Who Knew Infinity,” strikes you as a filmed play, you’re right. The film is based on a 2009 stage play by Mark St. Germain. That was based on a book “The Question of God” by Harvard professor of clinical psychiatry Armand Nicholi, which I have not read. The film, which is claustrophobic to say the least, is set for the most part at Freud’s London residence in the weeks before his death from oral cancer.

The film dramatizes a fictional meeting between pioneering psychologist and atheist Sigmund Freud (Anthony Hopkins) and author, devout Christian theologian and Cambridge and Oxford professor C.S Lewis (Matthew Goode, “Watchmen”) two days after the start of World War II. The apparent purpose of the meeting is for Freud and Lewis aka Jack to debate the existence of God. If the prospect of such a debate makes you long to hit the pillow, you are not alone, and I must confess I had a hard time keeping my eyes open watching this, in spite of the great acting talent involved.

Hopkins, who has played kings, popes, gods and an immortal serial killer in his illustrious career – and even once played Lewis opposite Debra Winger in the charming 1993 romance “Shadowlands” – does not find much of substance in Freud, except for an Austrian accent. Goode for his part plays Lewis with sufficient starchiness, until the author of “The Chronicles of Narnia” warms up to his Jewish interrogator and becomes somewhat less stiff.

The thing that causes the two to open up a bit is that Freud is suffering great pain caused by his disease and from a prosthesis in his mouth that he struggles to remove. He is also taking morphine regularly for his pain. In between pronouncements regarding the nature of life and the universe, Freud and Lewis discuss father figures, sex and Lewis’s experiences as an infantry soldier during World War I. The latter will be accompanied by flashbacks to Lewis in the trenches. Yes, Jack will tell Freud of his meetings with J.R.R. Tolkien and other members of the “Inklings.”

In other developments, Freud and Lewis will enter an underground bomb shelter, where Lewis will have an anxiety attack, recalling his experiences in the war. Using techniques he has developed with his patients, Freud will help Lewis to recover from this attack, something that causes them men to warm up even more to one another. We will also meet Freud’s daughter and pioneering child psychologist Anna Freud (Liv Lisa Fries), who is both overly dependent upon her famous father and secretly having an affair with another woman and fellow child psychologist Dorothy Burlingham (Jodi Balfour). Anna fears her father’s opinion of her if he learns of her homosexuality.

On the whole, “Freud’s Last Session” really does not amount to much, in spite of the great talent involved. If I were a psychologist, I would say that Brown, who adapted Germain’s play to the screen, needs to have his head examined if he thinks having two great fictionalized men meet to talk about life is enough to build a film around. If you’re going to fictionalize this sort of thing, you might as well use God and the Devil as your interlocutors and have Hopkins play both roles.

(“Freud’s Last Session” contains mature and sexual themes and violent images)

“Freud’s Last Session”

Rated PG-13. At the AMC Boston Common. Grade: B-