John le Carré, whose bestselling novels about the chilly world of Cold War espionage were the basis for a long series of popular film and TV adaptations, has died of pneumonia. He was 89.

Le Carré’s literary agency, Curtis Brown, announced his death on Dec. 13 via Twitter. The beloved storyteller, whose real name was David Cornwell, was a favorite among writers and screenwriters for the naturally cinematic touches and propulsive narratives he delivered over a career that spanned a half century and 25 novels, the most recent of which was published in 2019, three days after his 88th birthday.

“It is with great sadness that we must confirm that David Cornwell — John le Carré — passed away from pneumonia last Saturday night after a short battle with the illness… We all grieve deeply his passing. Our thanks go to the wonderful NHS team at the Royal Cornwall hospital in Truro for the care and compassion he was shown throughout his stay. We know they share our sadness.”

The writer, who had served in Great Britain’s intelligence agencies MI5 and MI6 in the years following the revelation of Russian double agent Kim Philby’s calamitous activities within the English spy network, began his writing career in the early ‘60s with two mysteries featuring British spy George Smiley.

Smiley reappeared in a minor role in le Carré’s breakthrough novel “The Spy Who Came In From the Cold” (1963), the international hit in which the novelist crystallized his career-long depiction of international intelligence as a murderous bureaucracy rife with duplicity and perfidy.

In his notes to the Criterion Collection edition of Martin Ritt’s 1965 screen adaptation of that book, critic Michael Sragow noted that le Carré’s work served as a kind of realist rebuke to the fantastical flash of Ian Fleming’s superhuman agent James Bond, then at the peak of his worldwide popularity.

Sragow wrote, “Le Carré’s view of espionage as an extension of the ugly, soul-grinding side of Cold War politics was more than a slap at the Bond books’ Byronic derring-do and the movies’ glamour, gimmickry, and jet-setting. It read like an exposé of the spy game’s dirty little secrets.”

(Ironically, one le Carré adaptation, 1990’s “The Russia House,” would star the original screen Bond, Sean Connery, while another, 2001’s “The Tailor of Panama,” was toplined by latter-day 007 Pierce Brosnan.)

In recent years, le Carre’s sons, writers Simon Cornwell and Stephen Cornwell, produced TV adaptations of their fathers work for global audiences through their Ink Factory banner. The 2016 limited series rendition of “The Night Manager,” which aired on AMC in the U.S. and  earned an Emmy award for director Susanne Bier and Emmy noms for stars Tim Hiddleston, Hugh Laurie and Olivia Colman.

Operating in the sphere previously occupied by Graham Greene, le Carré was the author of popular entertainments that nonetheless attracted serious critical scrutiny and the praise of his literary contemporaries. Philip Roth lauded his semi-autobiographical 1986 book “A Perfect Spy” as “the best English novel since the war.”

For his part, le Carré found the spy trade a natural subject. He wrote in “The Pigeon Tunnel,” his 2016 memoir, “Spying and novel writing are made for each other. Both call for a ready eye for human transgression and the many routes to betrayal.”

Though he was a fixture on bestseller lists until the end of his life, the prolific le Carré may have witnessed his greatest popularity in the ‘70s, when the trilogy “Tinker Tailor Soldier Spy” (1974), “The Honourable Schoolboy” (1977) and “Smiley’s People” (1979), about the pursuit of George Smiley’s nemesis, Soviet spymaster “Karla,” reaped critical acclaim and massive sales.

Smiley would become le Carré’s most durable creation: The savvy denizen of “the Circus” appeared in nine novels, including 2017’s “A Legacy of Spies,” a sequel of sorts to “The Spy Who Came In From the Cold.” The character was portrayed by such top-flight actors as Alec Guinness (in two TV adaptations); Gary Oldman (nominated for an Oscar for his work in Tomas Alfredson’s 2011 feature version of “Tinker Tailor Soldier Spy”); James Mason and Denholm Elliott.

The 1983 novel “The Little Drummer Girl,” about a young actress who infiltrates a Palestinian terrorist cell, was filmed twice: by George Roy Hill in a poorly received 1984 feature starring Diane Keaton, and as a widely praised 2018 limited series for AMC by director Park Chan-wook with Florence Pugh in the lead role.

“The Looking Glass War,” “The Constant Gardener” “A Most Wanted Man” and “Our Kind of Traitor” also made their way to the big screen, while “A Perfect Spy” and “The Night Manager” ran as multi-part TV dramas.

Le Carré wrote the screenplays for “A Murder of Quality” (1991) and (with John Boorman and Andrew Davies) “The Tailor of Panama.” Possibly with a wink at his countryman Alfred Hitchcock, le Carré took mostly uncredited bit parts in five adaptations of his work, first appearing in front of the camera in the ’84 version of “The Little Drummer Girl” under his given name.

David Cornwell was born Oct. 19, 1931 in Poole, Dorset. He had a rough upbringing: His mother deserted the family when he was five, and his father was an abusive small-time con man and associate of the notorious British mobsters Ronnie and Reggie Kray. He was educated as an undergraduate at two English boarding schools.

He was recruited into the British Army Intellligence Corps as a 17-year-old student at Switzerland’s University of Bern, serving as an interrogator of East German defectors. At Oxford’s Lincoln College in the early ‘50s at the height of the Cold War, he spied on left-wing political groups for MI5, the British Security Service. (The school’s alumni site identifies Lincoln College rector Vivian Green as the inspiration for George Smiley.) He transferred to MI6, the Secret Intelligence Service, in 1960.

In his role as an intelligence officer, sometimes working under diplomatic cover and frequently in contact with prominent foreign agents, the aspiring novelist found the theme for his writing. As he wrote in his memoir, “Rule one of the Cold War: nothing, absolutely nothing, is what it seems.”

He abandoned his work in intelligence after the success of “The Spy Who Came In From the Cold,” but the clash between the spy underworlds of East and West fed the majority of le Carré’s novels through the fall of Soviet communist in 1989.

His later plots  — many of them inspired by his travels around the globe — turned on the international arms and drug trade (“The Night Manager,” 1993), Central American intrigue (“The Tailor of Panama,” 1996) and Russian gangsters and money launderers (“Our Kind of Traitor,” 2010).

In 2019, le Carré published his 25th novel, “Agent Running in the Field.”

In addition to sons Simon and Stephen, le Carre is survived by his wife, editor Valerie Jane Eustace; their son, novelist Nick Harkaway; and another son from his first marriage.