The banker Marivol looks like a tailor, Lambinet. Gangsters threaten the first, who hires the second as a double. The latter accepts ignoring everything. When he learns that he will be the target of killers, the unfortunate man begins to live in terror.
Honorin is the simple and naive stage manager of a traveling theatre troupe, whose one ambition is to once play the role of the cavalier in the opera "Francis I, or the Loves of the Beautiful Ferroniere". A hypnotist puts him to sleep and in his dreams he is transplanted to the days of the Renaissance. There, among other items, he is made a Duke by Henri VIII, fights a duel and survives a series of medieval tortures, while also bestowing some 20th century blessings on the court of Francis I.
