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M has requested permission to let a prisoner on death row, in maximum security "escape." He is Joseph Heurtin, convicted of having killed a rich American, Mrs. Henderson, and her French maid, Élise Chatrier, at Saint-Cloud. His fingerprints and footprints were found everywhere, and he'd been seen in the neighborhood at the time, and had dropped a Paris-Saint-Cloud ticket. But he had no motive and nothing was stolen. He refused to say anything except that he didn't kill them. M is convinced that "he's either mad or innocent", and that someone else is involved.
Sure enough, Heurtin doesn't seem surprised to find the note telling of his escape plan, and the day after his escape a newspaper receives a note saying it was a police setup obviously from someone who knew something. The paper of the note was from the American bar at the Coupole, where M goes and sees Johann Radek, a Czech medical student. Heurtin, who had managed to elude his police followers, seems to be waiting outside for Radek, who has himself arrested for failing to pay his bill.
From then on Radek is virtually outright about his challenge to M to find some connection of himself to the murders. He gives M banknotes which can easily be traced to William Kirby, Henderson's nephew, who had also been in the Coupole. M goes back to Saint-Cloud, and finds William-Kirby in the house, but by the time he reaches him he's killed himself, shot in the head. Radek taunts M, who continues to silently follow him everywhere. Finally they return to the Citanguette, where Heurtin had first slept on escaping from the Santé, and they see Mrs. Kirby go to his room and tear up a mattress. They then follow her taxi to Saint-Cloud, where she goes into the house, returning in half an hour with a small package. But M refuses to follow her and brings Radek into the house, where he reveals Edna Reichberg, Kirby's mistress and his wife's friend, in a closet. Radek realizes he's caught, and shoots at M, but M has had the bullets changed.
Radek had overheard Kirby boast that he'd pay 100,000 francs to someone who'd kill his aunt, and secretly replied by note, getting the key to the house. He'd killed the two women, and gotten Heurtin there on the ruse of a burglary, forcing him to leave tracks and fingerprints, and eventually, to be convicted. Finally, once Heurtin has escaped, Radek had written to Kirby for the money, and received it, then had Kirby go out to the house on some pretext, hoping M would find him there. But M had figured things out, and intercepted letters from Radek to Mrs. Kirby and Edna, sending them there on his own. Radek, with little time to live because of a disease, was executed in the end; had wanted someone to appreciate his cleverness.
Maigret of the Month: May, 2004