Detective Chief Inspector James Japp (later Assistant Commissioner Japp) is a fictional character who appears in several of Agatha Christie's novels featuring Hercule Poirot.
Japp's career in the Poirot novels extends into the 1930s but, like Hastings, he disappeared from Christie's writing thereafter. A police officer somewhat similar in character (Superintendent Spence) was introduced as a significant recurring character in the later Poirot novels.
Japp appears in Christie's stage play Black Coffee, written in 1929. He remarks to Poirot that it has been a "long time" since they last met, in connection with "that Welsh case", which is not otherwise identified.
Inspector Japp is also briefly mentioned in the Tommy and Tuppence book The Secret Adversary; his card is brought to Julius Hersheimmer at the end of chapter five.
Like those of Miss Lemon and Arthur Hastings, the role of Inspector Japp in Poirot's career has been exaggerated by adaptations of Christie's original novels; specifically by the TV series Agatha Christie's Poirot, where these characters are often introduced into stories that did not originally feature them.
Japp has been depicted in seven novels written by Christie, all featuring Hercule Poirot:The Mysterious Affair at Styles (1920)
The Big Four (1927)
Peril at End House (1932)
Lord Edgware Dies (1933), also known as Thirteen at Dinner
Death in the Clouds (1935), also known as Death in the Air
The A.B.C. Murders (1936), also known as The Alphabet Murders
One, Two, Buckle My Shoe (1940), also known as An Overdose of Death and The Patriotic Murders. This is his last appearance in any work by Christie.
Japp was mentioned by Colonel Weston in Evil Under the Sun, the next book in the Poirot series after his final appearance. Japp is also mentioned in the novel "Taken at the Flood" by Superintendent Spence during a conversation with Hercule Poirot.
In most of these appearances, Japp is a minor character with minimal interactions with Poirot or involvement in the plot. However, Japp emerges as a major character and partner to Poirot in Lord Edgware Dies. He returns in this capacity in Death in the Clouds and One, Two, Buckle My Shoe, before being written out of the series. In number of appearances, Japp is comparable to Arthur Hastings who was featured in eight of the Poirot novels.
Japp also appears in Charles Osborne's novelisation of Christie's 1929 stage play Black Coffee.
James Japp, while being a competent detective, is no match for Poirot; he frequently finds himself a step behind the great detective but has developed a grudging respect for the man's abilities over their years together. Japp and Hastings often commiserate on their confusion and inability to keep up with Poirot on cases. At times, Japp cannily plays upon Poirot's ego in order to nudge the detective into taking up cases, but in such ways as Poirot does not seem to realize that Japp is maneuvering him.
Japp and Hastings are also generally astonished to find that Poirot cannot understand anything typically English (like cricket, which he maintains is utter nonsense).
The role of Japp is played by Philip Jackson in the British TV series Agatha Christie's Poirot, where Hercule Poirot's character is played by David Suchet. Before Suchet took on the role of Poirot, he had previously played Japp himself in the 1985 film Thirteen at Dinner, where Peter Ustinov played Poirot. Philip Jackson also plays Japp alongside John Moffat's Poirot in an ongoing series of BBC Radio adaptations, produced contemporaneously with the Suchet TV series. The portrayal of Philip Jackson is considered to be one of the best and most popular portrayals of Japp to date. Jackson portrays Japp as working-class and 'thoroughly British', not very intelligent but an extremely diligent, canny and active police officer with a good but rather dry sense of humour, characteristics which often serve as a perfect foil to Poirot's personality, who is intelligent, elegant, upper-class but rather slow in movements and of a very serious nature.
Japp is played by Melville Cooper in the 1931 film adaptation of Christie's stage play Black Coffee.
As the word Jap is pronounced in the same way as the chief inspector's name, he was renamed Inspector Sharp (シャープ警部, Shaapu-kebu) in the Japanese anime series Agatha Christie's Great Detectives Poirot and Marple (NHK, 2004).
In the Professor Layton series of puzzle video games for the NintendoDS and Nintendo3DS, the fictional Scotland Yard chief inspector Chelmey appears visually and contextually as a comically incompetent caricature of Inspector Japp as played by Philip Jackson.