by Mark Hodder

  • An introduction to this popular old character for the benefit of new readers.

Leon Kestrel is an American actor, an absolute master of disguise, and an unsurpassed mimic and impersonator. His real features are indeterminate. He inspires absolute loyalty. His significant others are: The War Profits Liquidation Syndicate, Fifette Bierce aka The Princess Pretence, Father Bierce (her father), Madrano the Steeplejack, Shanghai Jim, Semiramis the Greek, Marinotte, and Beaudelaire.

The character was created by Lewis Jackson (Jack Lewis).

Leon Kestrel

In the UNION JACK, Leon Kestrel is described as follows:

'Never before, in a lifetime of combat with crime of every kind, has Sexton Blake found himself opposed to a Syndicate so sinister and menacing as that created and controlled by the perverted genius of Leon Kestrel.

Once an actor of immense promise in America, Kestrel, drawn to crime by some queer mental kink, has brought the art of make-up and disguise to a pitch of perfection hitherto undreamed of. This uncanny skill, allied to a faculty for perfect acting, and strengthened by the beauty and disarming personality of Fifette Bierce, his principal accomplice, has enabled Kestrel to bring off criminal coups characterised by amazing audacity, and crowned only too often with a success that has been the despair of Scotland Yard and other police forces of the world.

On countless occasions Sexton Blake has crossed swords with Leon Kestrel and the coterie of clever criminals who form his "Inner Circle." Many times he has succeeded in thwarting them and in bringing their schemes to naught.

But always the elusive Kestrel himself has evaded capture, and escaped to remobilise his forces, and devise some fresh villainy, professing, with sardonic humour, a keen contempt for the police, and an amused tolerance for Blake's campaign against him.'

There is perhaps a further clue to the 'queer mental kink' that drove him to crime in THE AMAZING CASE OF THE BLIND FIDDLER (Union Jack issue 668, 1916). Here we learn that Kestrel, in his acting days, fell for a singer named Charmian Connellan. After she spurned him in May 1905 at the Theatre Metropole, New York, he never acted on stage again. Could it be that this rejection affected him so deeply as to drive him to a life of crime?


1. The Case of the Cataleptic (UNION JACK issue 620, 1915)
The Kestrel gang kill an old man so that his estates are inherited by one of his more disreputable relatives. When they try to frame his nephew for the crime, Sexton Blake becomes involved. He foils the plot but fails to capture Kestrel.

2. The Case of the Chinese Mascot (UNION JACK issue 641, 1916)

3. The Case of the Missing Airman (UNION JACK issue 646, 1916)
An aeronaut named Prendergast vanishes with top secret blueprints and Sexton Blake's initial invesigation seems to suggest that he has faked his own abduction. Further clues soon reveal that Kestrel is behind the mystery. Blake solves the case and wins an aerial dogfight with the Master Mummer. Kestrel parachutes to safety and escapes.

4. '913' The Case of the Aniline Formula (UNION JACK issue 651, 1916)
Kestrel frees Shanghai Jim from Bleakmoor Prison and they both help a chemist to kill a rival who has invented a new formula for dye. Sexton Blake solves the mystery of the murder and catches the chemist but Kestrel and Shanghai Jim escape.

5. The Affair of the Dutch Merchant (UNION JACK issue 655, 1916)
Leon Kestrel teams up with a crooked diamond merchant from Holland to fake the theft of some jewels then claim the insurance. Sexton Blake foils the plan and arrests the Dutchman but Kestrel gets away.

6. The Mystery of Martin Esher (UNION JACK issue 662, 1916)
Kestrel sends some of his henchmen to steal plans from a government inspector but they are defeated by the man's neighbour, an insane illusionist. Sexton Blake also falls foul of the madman and barely escapes with his life.

7. The Amazing Case of the Blind Fiddler (UNION JACK issue 668, 1916)
Kestrel impersonates a blind fiddler in order to murder the man who his one-time sweetheart married. He succeeds despite Sexton Blake's attempt to stop him.

8. The Case of the White Fugitive (UNION JACK issue 673, 1916)
Mona McArthur, who worked with Kestrel during THE CASE OF THE MISSING AIRMAN, is helped to escape the criminal's influence by Sexton Blake and the airman, Jim Prendergast. Taking her father with her, she flees to Australia to begin a new life. Kestrel avoids a trap set by the detective.

9. The Fool's Highway (UNION JACK issue 677, 1916)
Kestrel and members of his gang try to drive a rich chemist insane by tormenting his conscience with regard to a powerful explosive he has invented. If they succeed, the man's son will inherit his fortune — and the son is a drug addict, which makes him easy to fleece. The chemist, though, is friends with Sexton Blake, and the detective foils the scheme and captures two of Kestrel's gang.

10. The Poison Fumes (UNION JACK issue 684, 1916)
Kestrel is commissioned by an American metals company to kill a financier who opposes a merger that would corner the market to the disadvantage of allied forces. The Master Mummer succeeds but Sexton Blake intercedes before Kestrel can be paid. The villain escapes but the American company has been exposed and the merger will not proceed.

11. The Great Hoax (UNION JACK issue 689, 1916)
Kestrel teams up with Fifito Madrano and, posing as film actors, they carry off a huge heist in Hatton Gardens. Kestrel kidnaps Tinker and tells Blake that the penalty for his interference will be the lad's death. Blake, however, locates the Master Mummer's hideout and, assisted by Detective-Inspector Harker, he raids the place and recovers his assistant and the jewels. Kestrel and Madrano escape by means of a daring stunt.

12. The Great Office Mystery (UNION JACK issue 711, 1917)
Leon Kestrel and Fifito Madrano warn an engineer that they intend to steal the schematics to his new invention, even giving him the date that the burglary will occur. Sexton Blake and the police guard the man's office but Kestrel nevertheless manages to commit the crime. By using a prototype of the invention, Blake is able to locate the villain while he is selling the plans to a German agent. A pursuit follows, during which the agent is killed and the documents recovered. Kestrel and Madrano, however, evade capture.

14. The Strange Case of the Naval Lieutenant (THE UNION JACK issue 815, 1919)

15. The Case of the Decoy (THE UNION JACK issue 825, 1919)

16. The Riddle of the Rector's Wife (THE UNION JACK issue 833,1919)

17. The Case of the Four Detectives (THE UNION JACK issue 836, 1919)

18. The Isle of Revenge (THE UNION JACK issue 843, 1919)

19. The Red Heart of the Incas (THE SEXTON BLAKE LIBRARY 1st series issue 86, 1919)

20. The Case of the Transatlantic Flyers (THE SEXTON BLAKE LIBRARY 1st series issue 90, 1919)

21. The Kestrel Syndicate (THE SEXTON BLAKE LIBRARY 1st series issue 95, 1919)

22. The Chink in the Armour (THE SEXTON BLAKE LIBRARY 1st series issue 106, 1919)

23. Kestrel's Great Bluff (THE UNION JACK issue 848, 1920)

24. The Dance of Disaster (THE UNION JACK issue 864, 1920)

25. The Case of the Bogus Judge (THE UNION JACK issue 886, 1920)

26. The Mist of Sleep (THE UNION JACK issue 890, 1920)

27. The Case of the Paralysed Man (THE UNION JACK issue 891,1920)

28. A Price on His Head (THE UNION JACK issue 897, 1920)

29. The Jewels of Wu Ling (THE SEXTON BLAKE LIBRARY 1st series issue 111, 1920)
A Chinaman named Wu Ling comes under suspicion when his wife is shot dead. He tells Sexton Blake how he had stolen a diamond from a mine in South Africa only to be cheated out of it by Kestrel; how Kestrel killed his wife; and how he, Wu Ling, has vowed revenge. Kestrel, however, has kidnapped the Chinaman's child, so when Blake corners the criminal mastermind, Wu Ling prevents his capture. Blake disguises himself as the celestial and tricks Kestrel into revealing the whereabouts of the child. He frightens and humiliates Kestrel but, unfortunately, cannot prevent the crook's last-minute escape.

30. The Affair of the World's Champion (THE SEXTON BLAKE LIBRARY 1st series issue 115, 1920)

31. The Affair of the Oriental Doctor (THE SEXTON BLAKE LIBRARY 1st series issue 127, 1920)

32. The Kestrel's Claw (THE SEXTON BLAKE LIBRARY 1st series issue 139, 1920)

33. The Mystery of the X.O.4. (THE SEXTON BLAKE LIBRARY 1st series issue 147, 1920)

34. The False Alibi (THE SEXTON BLAKE LIBRARY 1st series issue 155, 1920)

35. The Kestrel's Prey! (THE UNION JACK issue 913, 1921)

36. Kestrel's Intrigue (THE UNION JACK issue 922, 1921)

37. Prince Pretence (THE UNION JACK issue 929, 1921)

38. Kestrel's Conspiracy (THE SEXTON BLAKE LIBRARY 1st series issue 160, 1921)

39. The Lady of Ravensedge (THE SEXTON BLAKE LIBRARY 1st series issue 172, 1921)

40. Threatened By Three (THE UNION JACK issue 956, 1922)
Sexton Blake investigates how transcripts of high level government meetings are being sold to enemy powers. He quickly asserts that Leon Kestrel's War Profits Liquidation Syndicate is at work and has allied with Prince Wu Ling and Zenith the Albino. The criminal trio attempt to administer a drug that will rob Blake of his intellect but Detective-Inspectors Coutts and Harker come to the detective's aid. The villains escape and capture Mademoiselle Yvonne. Blake rescues her, captures Zenith, and hands the villain over to Coutts. However, the Scotland Yard man turns out to be Kestrel and the master-criminals flee in a dirigible. Tinker manages to get aboard, and when Kestrel, Zenith and Wu Ling parachute onto a foreign steam ship and make a getaway, the youngster reveals that he picked Kestrel's pocket and has got the stolen papers.

41. The Convict Millionaire (THE UNION JACK issue 958, 1922)

42. The White Sentinel (THE UNION JACK issue 961, 1922)

43. In League Against Him (THE UNION JACK issue 969, 1922)
Leon Kestrel teams up with Zenith the Albino and Prince Wu Ling again and they set out to kill Sexton Blake. One of Kestrel's henchmen has invented a device that transmits radiation. He sets mechanisms in a house in Baker Street to send deadly beams into Blake's consulting room. The detective suspects he has been targeted when a professor he's questioning is badly injured in the room with no apparent cause. Blake disguises himself and visits the Thieves' Kitchen where he overhears Zenith, Kestrel and Wu Ling discussing the house where the deadly device is located. The police raid the place, the Lascelite projectors are destroyed, but the three crooks escape in a hot air balloon.

44. Double Crossed (THE UNION JACK issue 983, 1922)

45. The Thousandth Chance (THE UNION JACK issue 1,000, 1922)
Kestrel joins with Huxton Rymer, the Three Musketeers, Prince Wu Ling, Mary Trent, the Black Duchess, Zenith the Albino, George Marsden Plummer and Professor Kew to rob Sexton Blake of his art collection. After they succeed, Wu Ling telephones Baker Street and offers the detective information about his stolen property in return for an ancient Ling-tse vase of great symbolic importance. Sir Gordon Saddler advises Blake to accept. The detective does so and the exchange is made but Saddler performs a stunt that deprives Wu Ling of the vase. With an armistice declared, Sexton Blake visits the gathered crooks at Abbey Towers and regains his valuables.

46. The Case of the Bendigo Heirloom (THE SEXTON BLAKE LIBRARY 1st series issue 218, 1922)

47. The Fallen Star (THE SEXTON BLAKE LIBRARY 1st series issue 238, 1922)

48. The Return of Beaudelaire (THE UNION JACK issue 1,024, 1923)

49. The Shadow of the Past (THE UNION JACK issue 1,053, 1923)

50. The House of Fear (THE SEXTON BLAKE LIBRARY 296, 1923)

51. The Syndicate for Sale or Kestrel Betrayed (THE UNION JACK issue 1,076, 1924)

52. The Strange Case of the Runaway Surgeon (THE UNION JACK issue 1,084, 1924)

53. The Law of the Claw (THE UNION JACK issue 1,099, 1924)

54. The Mysterious Affair of the Vanishing Stones (THE UNION JACK 1,204, 1926)

55. The Problem of the Gardener's Cottage (THE UNION JACK issue 1,205, 1926)

56. The Fox of Pennyfields (THE UNION JACK issues 1,231 to 1,235, 1927)

57. The Case of the Disqualified Derby (THE UNION JACK issue 1,232, 1927)

58. The Monster of Paris (DETECTIVE WEEKLY issue 13, 1933)
Nigel Blake turns up on Sexton Blake's doorstep, shot through the chest, and is rushed to hospital. Blake begins investigating and learns that Leon Kestrel has come out of retirement, has gained possession of the jewels Nigel had stolen, and is now planning to obtain plans for a new type of submarine. The trail leads to Paris where the detective encounters Baudelaire, who gives him valuable information regarding Kestrel's whereabouts. Blake regains possession of the jewels then foils the scheme to sell the submarine blueprints. Kestrel, however, gets away.

59. The Panic Liner Plot (DETECTIVE WEEKLY issue 73, 1934)

60. The Case of the Biscay Pirate (THE SEXTON BLAKE LIBRARY 65, 1944)