The Affair of the Sinister Stranger

This flow traces a staged medical inquiry that becomes a test of the agency's loyalty to its instructions and its ability to detect an impostor.

increasingBearing stren­gth in each eventdecreasing

A Blue Letter Arrives

A Blue Letter Arrives The Expected Signal The Russian-stamped letter matches Carter's warning about a coded message. Tommy prepares to verify the number beneath the stamp and pass the correspondence to his chief. A Visitor Interrupts A burly stranger enters while the letter is exposed. His repeated glances at it make Tuppence suspect that the message has already drawn hostile attention.

The Poison Research Tale

The Poison Research Tale An Elaborate Complaint The stranger calling himself Dr. Charles Bower describes searches for deadly alkaloid notes and proposes a midnight meeting. Tommy recognizes the story's theatrical quality. Tuppence's Warning Tuppence identifies the visitor's limp and implausible account as signs of a setup. Their disagreement is not about whether danger exists but how directly to confront it.

Dymchurch's Reassurance

Dymchurch's Reassurance Borrowed Authority Inspector Dymchurch claims that Marriot asked him to watch the agency. He warns Tommy not to attend the supposed meeting and offers an alternative trap at the office. Trust Exploited His official manner persuades Tommy to cooperate. The impostor's success depends on making the correct warning sound more reliable than the suspicious client.

A Captive in His Office

A Captive in His Office Betrayal Revealed Dymchurch and an accomplice seize Tommy and search the agency. The supposed inspector reveals himself as a foreign operative who knows the office is a cover. A Demand for Tuppence The gang believes she has the letter and forces Tommy to summon her. He sends a warning in the form of a note that uses their fictional detective identities.

A False Envelope

A False Envelope A Planned Deception Tuppence comes with an empty envelope, having already forwarded the original letter and alerted Inspector Marriot. She uses the enemy's confidence in its own plan against it. Arrest and Disclosure Marriot's team arrests the conspirators. The episode strengthens the agency's reputation and teaches Tommy that Tuppence can anticipate danger as well as share it.

A quiet afternoon at the office

That afternoon

Later that afternoon

That evening

Minutes later