Few television series have enjoyed the tremendous success of “Columbo.” Created by Richard Levinson and William Link, it was a rarity among mystery stories and dramas in that the audience knew from the outset who committed the murder. The suspense was in discovering where the killer made a mistake and how the titular detective would ferret it out.

Although clearly an attractive format, the extraordinary ratings and enthusiasm viewers had for the show was due in great part to Peter Falk, who played the homicide detective for so many years. His filthy, rumpled trench coat became famous. The one he wore on the early programs was reputed to have been his own and — I give you my word this is true — when he visited my bookshop some years ago, on a rainy Saturday afternoon, he was wearing exactly the trench coat we had all come to know. Equally predictable was his habit, when almost out the door, of stopping and saying “just one more thing,” which drove his prey crazy.

But did you know that Mr. Falk was not the first choice to play the iconic detective? That was Thomas Mitchell, the famous movie character actor who had the role in “Prescription: Murder,” a stage play featuring Columbo that ran for half a year, but he passed away. Lee J. Cobb was suggested, but he couldn’t do it. NBC finally offered the role to Bing Crosby, who turned it down because a series commitment would have interfered with his addiction to golf.

And so, on the night of February 28, 1968, Mr. Falk made his debut in the role with which he will forever be linked.

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One of the most chilling films noirs of the 1970s is “Taxi Driver,” Martin Scorsese’s neo-expressionistic riff on the post-Vietnam era and its dark vision. Robert De Niro’s portrayal of the paranoid and psychopathic Travis Bickle helped cement his status as one of America’s greatest actors.

Among the several scenes that burn in the memory, none are more powerful than Bickle’s monologue in front of a mirror as he confronts an imaginary adversary. “Are you talkin’ to me? What? You talkin’ to me? You’re not talkin’ to me!”

Well, did you know the entire scene was ad-libbed by Mr. De Niro? Although Paul Schrader wrote the script, Mr. De Niro simply took over for the moment and let his evidently dark imagination improvise.

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It would not be at all a stretch to say that Nero Wolfe is the most beloved of all American detectives. I can think of no author who maintained Rex Stout’s exceptionally high level of detective stories for such a long time. With nearly four dozen books devoted to Wolfe and Archie Goodwin, plus another dozen or so novels, one would think Stout devoted his entire life to putting words on paper.

But did you know that the school banking system, employed by more than 400 cities for decades, was invented by Stout and made him wealthy before he created Wolfe in 1934? Stout, a prodigy, had read the Bible from cover to cover twice by the age of 4, had read a thousand classics by the age of 10, and was the state spelling champion in Kansas when he was 13.

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The most famous criminal in literature is A.J. Raffles, E.W. Hornung’s creation, who, for a short time, rivaled Sherlock Holmes in popularity. The gentleman jewel thief first appeared in “The Amateur Cracksman” in 1898, followed by only three additional books. Four films were made about him with such stars as John Barrymore, Ronald Colman, and David Niven as the eponymous protagonist.

But did you know that Hornung was the brother-in-law of Arthur Conan Doyle? The creator of Holmes was well-known to be a bit stiff, as humorous as Verdi’s “Requiem,” and it seems likely that Hornung created the antithesis of the great detective in order to tweak his wife’s brother’s nose.

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One of the leading intellectuals of the past half-century is Gore Vidal. Equally famous for his satirical novels and pompous pronouncements on the state of American culture, Mr. Vidal served as a member of President Kennedy’s Council for the Arts in the 1960s.

But did you know that he wrote three pseudonymous mystery novels? Under the byline Edgar Box, he produced a series about Peter Cutler Sergeant II, a public relations specialist who is surprised again and again to be embroiled in murders. Negligible as detective stories, Mr. Vidal’s nasty wit nonetheless makes them entertaining novels.

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One of the most famous and popular bylines of American detective fiction is Ellery Queen, the name of the author as well as of the detective. It is well-known that the Queen by-line was the joint pseudonym of two Brooklyn-born cousins, Frederic Dannay and Manfred B. Lee.

In the 1930s, as the Queen collaboration was at the peak of its creative powers, another mystery writer, Barnaby Ross, produced four successful novels about Drury Lane. In an effort to garner publicity for their works, Queen and Ross donned black masks and debated about their books and other elements of mystery fiction.

But did you know that the Ross byline was another pseudonym of Dannay and Lee? Each cousin took the persona of one of the authors as they essentially debated themselves.

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It is difficult today to remember the shock with which Alfred Hitchcock’s “Psycho” was greeted in 1960. The apparent star of the film was Janet Leigh who, to the utter disbelief of the audience, was murdered about a third of the way into the movie. The notorious shower scene, with screeching music accompanying the violent slashing of a gigantic knife, leaves the actress’s eyes staring vacantly in death as blood washes down the drain.

But did you know that the blood splashed on the wall, on Miss Leigh’s body and in the bottom of the bathtub was actually Hershey’s chocolate syrup? Filmed in black and white, it had exactly the right color and texture.

This has been another dip into my bucket of useless information.

Mr. Penzler is the proprietor of the Mysterious Bookshop in Manhattan and the series editor of the annual “Best American Mystery Stories.” He can be reached at ottopenzler@mysteriousbookshop.com.