In the second episode of the trilogy Fantômas kidnaps distinguished scientist professor Marchand with the aim to develop a super weapon that will enable him to menace the world. Fantômas is also planning to abduct a second scientist, professor Lefebvre. Journalist Fandor develops an ingenious scheme whereby he disguises himself as Lefebvre and attends a scientific conference in Rome, Italy to lure Fantômas into attempting to kidnap him. The plan seems to work until commissaire Juve steps into the fray and as usual messes things up. Fantômas escapes in style using his Citroën DS with retractable wings that converts into an airplane in what amounts to one of the most unexpected and spectacular scenes of the genre.