Carr is generally regarded as one of the greatest writers of so-called "Golden Age" mysteries; complex, plot-driven stories in which the puzzle is paramount.

In short he can write" - Dorothy L. Sayers Carr's two major detective characters, Dr. Fell and Sir Henry Merrivale, are superficially quite similar.

A wealthy descendant of the "oldest baronetcy" in England, he is part of the Establishment (even though he frequently rails against it) and in the earlier novels is the director of the British Secret Service.

Many of the Merrivale novels, written using the Carter Dickson byline, rank with Carr's best work, including the much-praised The Judas Window (1938).

The novel The Crooked Hinge (1938) combines a seemingly impossible throat-slashing, witchcraft, a survivor of the ship Titanic, an eerie automaton modeled on Wolfgang von Kempelen's chess player, and a case similar to that of the Tichborne Claimant into what is often cited as one of the greatest classics of detective fiction.

Dr. Fell's own discourse on locked room mysteries in chapter 17 of The Hollow Man is acclaimed critically and is sometimes printed as a stand-alone essay in its own right.

The most famous of these, The Burning Court (1937), involves witchcraft, poisoning, and a body that disappears from a sealed crypt in suburban Philadelphia; it was the basis for the French movie La chambre ardente (1962).

Probably the best of them are in the Carter Dickson book, The Department of Queer Complaints (1940), although this does not include the brilliantly clever H.M. story The House in Goblin Wood or a successful pastiche which introduces Edgar Allan Poe as a detective.

The book, The Life of Sir Arthur Conan Doyle, was published during 1949 and received generally favorable reviews for its vigor and entertaining style.

The British novelist Kingsley Amis, for instance, writes in his essay, "My Favorite Sleuths", that Dr. Fell is one of the three great successors to Sherlock Holmes (the other two are Father Brown and Nero Wolfe) and that H.M., "according to me is an old bore."

Howard Haycraft, author of the seminal Murder for Pleasure: The Life and Times of the Detective Story, wrote during 1941 that H.M. or "The Old Man" was "the present writer's admitted favorite among contemporary fictional sleuths".

His 1943 half-hour radio play Cabin B-13 was expanded into a series on CBS during 1948–49[6] for which Carr wrote all 23 scripts, basing some on earlier works or re-presenting devices that Chesterton had used.

The 1943 play Cabin B-13 was also expanded into the script for the 1953 movie Dangerous Crossing, directed by Joseph M. Newman and featuring Michael Rennie and Jeanne Crain.

Carr worked extensively for BBC Radio during World War II, writing both mystery stories and propaganda scripts.