4 Agatha Christie Novels That Have Never Been Adapted for the Screen

Agatha Christie wrote some of the most adapted mysteries in history. Her novels have spawned dozens of films and TV shows. Four of them, however, remain stubbornly unadapted.

The Unadapted Quartet

The list includes Death Comes as the End, Destination Unknown, Passenger to Frankfurt, and Postern of Fate. Christie buffs have spent years arguing whether any of these can be turned into a viable production.

Death Comes as the End

Death Comes as the End is set in ancient Egypt around 2000 BC. It follows Renisenb, daughter of a priest, as she investigates the death of Nofret, her father’s concubine. Christie wrote it at the request of Egyptologist Stephen Glanville, drawing on her own research and trips to the Middle East with her second husband, archaeologist Max Mallowan.

The ending was changed at the insistence of Glanville and her publishers. She always regretted that decision.

Destination Unknown

Destination Unknown is a spy thriller involving missing scientists and a dying woman. It was published in the US as So Many Steps to Death. Reviews were mixed. One 1954 review in The Bulletin called the climax tame and the romance fabricated, but praised the vanishing act as “sizzling” and potentially plausible.

Warner Bros. Television bought the rights in 1979. Nothing came of it.

Passenger to Frankfurt

Passenger to Frankfurt was published in 1970, timed for Christie’s 80th birthday. It features Sir Stafford Nye, an English diplomat traveling home from Southeast Asia, who meets a woman claiming someone is trying to kill her. The twist: Adolf Hitler survives World War II by hiding in an asylum and fathering a son to continue his work.

Biographer Lucy Worsley described it as “utterly bonkers.” The New York Times wished someone had discouraged its publication. Dorothy Olding, Christie’s literary agent, called it “a bad imitation of a spy story and a damned weak one at that.”

Postern of Fate

Postern of Fate is the final Tommy and Tuppence novel, and according to Christie’s official website, the last novel she ever wrote. The elderly detective duo move into an old English village house with a collection of antique books. In one tome, Tuppence finds a message spelled out in underlined letters: “Mary Jordan did not die naturally.”

The setting recalls Ashfield, Christie’s childhood home in Torquay, England. Olding said of it: “Pretty ghastly, isn’t it?” She added, “Much worse than the last two… Poor dear, I wish there was a way for somebody to tell her that this shouldn’t be published — for her sake.”

Why They Stay Unadapted

Fans debate whether these novels are truly unfilmable. The ancient Egyptian setting of Death Comes as the End is cited as a barrier. One Reddit user noted, “Sure, they took Bette Davis to the Nile, but recreating Ancient Egypt is another level altogether.”

Some think Destination Unknown could work with the right tone. One user suggested a self-aware comedy along the lines of Romancing the Stone, noting the plot has “over-the-top James Bond potential.”

What Fans Want

Passenger to Frankfurt was read as a story that “feels like a story that belongs to our current moment,” with potential for a thriller adaptation.

The Tommy & Tuppence Question

Tommy and Tuppence’s future hangs on the upcoming BritBox series. If that brings the duo to screen, Christie’s backlog shrinks to three unadapted novels.

A Table of the Unadapted

The Verdict on the List

These novels are not failures. They are simply outliers. Christie’s official website presents them as part of her canon without apology. The adaptations may come eventually, or they may not.

Either way, the discussion is the point. Christie’s readers keep arguing about which of her lesser-known works deserve a second chance.

Agatha Christie · book adaptations · classic literature · mystery fiction · unadapted novels