Fifteen days have passed since the events at Maillot. Moréno is looking for clues to lead him to the Vampires, and reads in a paper that a Fontainebleau notary has been murdered by them; as he happens to possess a gaze with a terrible hypnotic power, he takes control of his new maid, Laura, to turn her into his slave. Meanwhile, Philippe and Mazamette happen to see a newsreel on the murder inquest, in which they spot Irma Vep and the Grand Vampire. They cycle to Fontainebleau to investigate. En route they spot an American tourist, Horatio Werner, riding fast into the forest, and follow him. He places a box under one of the boulders, and they take it. The Grand Vampire, who is staying in the Royal Hunt Hotel under the pseudonym of Count Kerlor, along with Irma in disguise as his son, Viscount Guy, reads in a paper that George Baldwin (Émile Keppens), an American millionaire, has been robbed of $200,000. Whoever can capture the criminal, Raphael Norton, who has fled to Europe with the actress Ethel Florid, will be awarded the unspent balance of the loot. “Kerlor” notices that Mr and Mrs. Werner, who are staying at the hotel, are distressed by this notice, and concludes that Mr. Werner is Raphael Norton. Philippe and Mazamette arrive at the hotel and find that the Vampires are based there. In a different hotel they force open the box and find Baldwin’s stolen money inside. Moréno comes to the Royal Hunt in disguise. While the Grand Vampire tells the hotel guests a story, Irma breaks into the Werners’ suite, finding a map leading to the box in the forest. When she leaves, she is captured and chloroformed by Moréno, who takes the map. While his gang take Irma away, he dresses his hypnotized maid, Laura, as Irma and tells her to give the Vampires the map. Once one of the Vampires (Miss Édith) follows the map to get the treasure, Moréno’s gang ambushes her, only to find that Philippe has already taken it. Moreno demands that the Grand Vampire ransom Irma Vep. In the early morning, the police raid the hotel and find that Werner is actually Norton, so Philippe and Mazamette win the money. Moréno falls in love with Irma and decides not to return her to the Grand Vampire. Instead, he hypnotizes her and causes her to write a confession of her involvement in the murders of the Fontainbleau notary (in this episode), Metadier (episode 4), the ballerina Marfa Koutiloff (episode 2), and Dr. Nox (episode 1). The Grand Vampire comes to meet Moréno, but Moréno by hypnotic command compels Irma to kill him. The episode ends with the now-wealthy Mazamette informing a dozen adoring journalists that “although vice is seldom punished, virtue is always rewarded”.