The Man Who Was Thursday is a thriller novel published in 1908 by the English author G.K. Chesterton. Subtitled A Nightmare, the book weaves together elements of mystery, comedic farce, and allegory around the threat of anarchy in turn-of-the-century London. For over a century after its publication, The Man Who Was Thursday inspired numerous adaptations, including a 1938 Mercury Theatre radio-play written by Orson Welles. Other works by Chesterton include Orthodoxy, The Ball and the Cross, and The Everlasting Man.

Plot Summary

Protagonist Gabriel Syme is a poet, philosopher, and detective for the New Detective Corps investigating an anarchy ring in Edwardian London. Through his connection with an anarchist named Lucian Gregory, Syme infiltrates a meeting of the Central Anarchist Council in London. He secures a place on the council which is made up of seven men, each named after a day of the week: the Secretary of the Council (Monday), Gogol (Tuesday), the Marquis de St. Eustache (Wednesday), Syme (Thursday), Professor de Worms (Friday), Dr. Bull (Saturday) and the President (Sunday). The Secretary escorts Syme to a local hotel where they meet the other five members of the council. Toward the end of the meeting, Sunday exposes Gogol as an undercover police officer. Sunday permits Gogol to leave but threatens to kill him if he ever reveals anything about the council.

Syme later learns that Professor de Worms and Dr. Bull are also undercover detectives and that the same shadowy figure recruited all three of them in the same manner. The three men turn their attention to the Marquis de St. Eustache, who is on his way to Paris to carry out the council’s plan to assassinate the Czar and the President of France. In Calais, the Marquis reveals to the group that he too is an undercover agent who hopes to catch Sunday as he disembarks a train. At the train station, a large group of people led by the Secretary pursues the detectives. The Secretary corners Syme and his companions to a jetty where he reveals that he is a Scotland Yard detective. This confirms that every member of the council aside from Sunday is an undercover agent.

Now joined by Gogol, the six detectives decide to confront Sunday at the council’s weekly breakfast meeting. After revealing his and the other detectives’ identities, the Secretary boldly asks, “[W]ho are you!?” (105). Sunday draws himself up to an enormous height and responds in a roaring voice, “Since the beginning of the world all men have hunted me like a wolf […] But I have never been caught yet” (105). He leaps over the balcony, but before he disappears, he tells them he was the man who made them all detectives.

Stunned, the policemen chase Sunday to the London Zoo. Sunday rides away atop an elephant before escaping in a hot air balloon. The six bedraggled men head off through a field in pursuit of the balloon. They see the balloon come down but do not see Sunday. As they make their way through the field, an immaculately-dressed valet tells them carriages await to bring them to his master’s house. When the detectives arrive at the house, they go to rooms that hold food, wine, and clothing. The valet hands Syme a Bible, points to a verse in Genesis, and tells him the clothing represents the day God created the sun and moon, or Thursday. Each of the six men’s costumes represent a day in the biblical story of the creation of the world.

Outside, there is a garden filled with people in elaborate costumes. At one end of the garden are seven thrones. The detectives sit in the order of the days of the week. Sunday finally enters, dressed in bright white, and sits on the middle throne. Slowly, the people leave the garden until the seven men are alone. Sunday says they have known and loved each other from the beginning of the world. He praises them as honorable men who have fought together valiantly. He also finally reveals his identity, saying, “I am the Sabbath, I am the peace of God” (123).

As the men recount the pain, fear, and suffering they endured on their journey, a figure dressed all in black walks toward them. Syme gasps when he recognizes the man as Lucian Gregory. Gregory announces he is the real anarchist, the destroyer, and declares his hatred for everyone and everything. He hates their power and their safety, accusing them of not suffering as he suffers. Syme turns to Sunday and asks if he has ever suffered. As Syme watches, Sunday grows “larger and larger, filling the whole sky; then everything [goes] black […] he [seems] to hear a distant voice saying […] ‘Can ye drink of the cup that I drink of?’” (126).

Suddenly, Syme finds himself walking on the road beside London’s Saffron Park, talking amiably with Gregory. Syme remembers Sunday’s face but doesn’t remember waking. He feels unusually happy, as if he possesses “some impossible good news” (126). As dawn breaks, he continues to walk until he sees Gregory’s sister, Rosamond, cutting lilacs in a garden by the side of the road.