Derrick Yale

Mr. Parr

Derrick Yale, a detective, and Mr. Parr, the leader of the Crimson Circle, are locked in a high-stakes battle of wits as hunter and hunted.

Thalia Drummond

Derrick Yale is romantically interested in Thalia Drummond, creating a love triangle with Felix Marl.

Felix Marl

Derrick Yale and Felix Marl are rivals both in their pursuit of Thalia Drummond and in their opposing roles as detective and criminal.

Harvey Froyant

Derrick Yale works alongside Harvey Froyant as a colleague in the investigation of the Crimson Circle.

Brabazon

Brabazon is an antagonist to Derrick Yale, opposing him as part of the Crimson Circle's efforts.

Mr. Parr

Derrick Yale, a detective, and Mr. Parr, the leader of the Crimson Circle, are locked in a high-stakes battle of wits as hunter and hunted.

Thalia Drummond

Derrick Yale is romantically interested in Thalia Drummond, creating a love triangle with Felix Marl.

Mr. Parr

Derrick Yale, a detective, and Mr. Parr, the leader of the Crimson Circle, are locked in a high-stakes battle of wits as hunter and hunted.

Thalia Drummond

Derrick Yale is romantically interested in Thalia Drummond, creating a love triangle with Felix Marl.

Felix Marl

Derrick Yale and Felix Marl are rivals both in their pursuit of Thalia Drummond and in their opposing roles as detective and criminal.

Felix Marl

Derrick Yale and Felix Marl are rivals both in their pursuit of Thalia Drummond and in their opposing roles as detective and criminal.

Harvey Froyant

Derrick Yale works alongside Harvey Froyant as a colleague in the investigation of the Crimson Circle.

The Crimson Circle

Appears as an investigator or authority figure dealing with the Crimson Circle.

Mr. Felix Marl

Observes Marl's fear from a distance, notes he reminds him of someone, and interprets the Crimson Circle mark as a sign of trouble.

The Girl Who Ran

Present on the terrace; warns of serious danger to Jim Beardmore and rushes to the scene after the shot.

VI: “Thalia Drummond Is a Crook”

Uses psychometry to identify a suspect named Sibly from a cartridge, discusses the case with Parr, and informs Jack Beardmore of the arrest.

The Stolen Idol

Silent listener during the pawnbroker interview; tries to soothe Jack after Thalia's arrest.

The Confession

Accompanies Parr to interrogate Sibly and skillfully extracts his confession.

Mr. Marl Squeezes a Little More

Visits the bank briefly; Thalia reports his presence to the Circle.

XVII: The Blower of Bubbles

Investigates Marl's murder, deduces the bubble poison method.

Thalia Accepts an Offer

Offers Thalia a job to observe her and gain information about the Crimson Circle; plans to intercept the ransom payment.

The Key of River House

Yale is discussed as a clever detective with psychometrical powers. He has engaged Thalia as his secretary and requested the key to Jack's riverside house.

River House

Reveals his knowledge of Thalia's visit to Parr, plans and executes a search of Beardmore's river house for Brabazon.

The Messenger of the Circle

Yale orchestrates the trap for the Crimson Circle's messenger, is overpowered and chloroformed in his office, and the money is stolen.

XXIII: The Woman in the Cupboard

Attacked and drugged in his office; the money he was guarding is stolen.

£10,000 Reward

Sees the reward poster on his way to the office and wonders about its effect on minor gang members.

The Tenant of River House

Mentioned as having searched River House earlier, nearly discovering Brabazon.

The Bottle of Chloroform

Thalia works for him as a secretary; mentioned as having put Parr up to the Marisburg Place job; Thalia plans to speak to him about Barnet.

Mr. Parr's Mother

Yale telephones Jack with information about the case and plans to visit Brabazon with Parr.

A Shot in the Night

Arrives after the shooting, reveals he received a Crimson Circle death threat, and discusses plans for the fourth of next month.

XXX: The Silencing of Froyant

Visits police headquarters, demonstrates his psychic abilities, and accompanies Parr to Froyant's house; discovers Froyant's body.

XXXI: Thalia Answers a Few Questions

Interrogates Thalia about her movements and the underground room at Froyant's house; reflects on her enigmatic personality.

A Trip to the Country

Attempts to exonerate Parr at headquarters; discusses the Sibly poisoning case with the Commissioner.

The Posters

Sends a telegram to Parr that turns out to be a fake; Parr later confirms with Yale that the wire was not genuine.

Blackmailing a Government

Meets Parr at Whitehall, expresses worry about the Crimson Circle's latest move, refuses to take sole command of the investigation, and later discusses the situation with Thalia Drummond.

Thalia Lunches with a Cabinet Minister

Discusses the investigation with Parr, lunches with the Commissioner to share suspicions about an insider at police headquarters, and dismisses Thalia from her secretarial position.

The Circle Meets

Mentioned by the Crimson Circle master as a source of considerable anxiety.

The Arrest of Thalia

Arrests Thalia Drummond for attempted murder of Raphael Willings.

A Prison Diet

Reports to Parr about Thalia's escape and the stabbing of Willings.

The Escape

Reads about Thalia's escape in the newspaper, rushes to headquarters, and later meets Parr to discuss the case and the found evidence.

Who Is the Crimson Circle?

Discovers his office and flat have been burgled by Thalia Drummond; reveals his theory that Thalia is the real leader of the Crimson Circle; is exposed as the Crimson Circle by Inspector Parr.

XLII: Mother

Captured by Parr's men; revealed to be the Crimson Circle leader Ferdinand Walter Lightman.

The Story Continued

Exposed as the Crimson Circle; his psychometric detective persona was a facade to manipulate victims and commit murders.