Antonio is a millionaire who spends his time conquering beautiful women aided by his faithful butler, Pablol. He tries to seduce the beautiful Marta, but when he realizes that she prepares a trap to force him to marry, Antonio disappears.

A gang of four poor underdogs plans a bankrobbery. The problems start when they try to make their plans reality and realize that they are robbing a fortune of various millions of pesetas.

Susana is an unappreciated, naive and somewhat clumsy orphan who has lived since she was a child at doña Engracia's house, because her mother died a few days after she was born. In this house, which also houses three nephews of doña Engracia without a penny to one's name, Susana is the maid of all. Economic necessities lead Engracia to rent a room. Felipe, a handsome man with a bad reputation, will reply to the ad.

Paris 1900. Sharing a house in the Bohemian District are Roberto, a fledgling Musician, who is composing an Opera with his friend the poet Victor Duval; and the beautiful Cossette, daughter of a retired tenor, who goes up and down the stairs, taking advantage of Roberto's music to train her voice. The young bohemian musician does not know Cosette, but hears her sing daily. Instead, she's in love with Roberto and follows his steps as a composer.

An antique hustler, a couple of thieves, one pickpocket, a seductive man ... These are the elements of the criminal gang led by "the Brain". Together they aim to make a big score that allows them to retire. "The Brain" master of manipulation, has assigned a role to each one separately, but only he knows all the secrets of the plan.

Mario Colomer, prime minister, is burdened by overwork. His problems seem solved when his assistants tell him about Juan Brandel, a possible substitute, just like him physically, but with a funnier and more adventurous personality. At first the plan seems to work and the politician begins to gain popularity. The plot thickens when the 'original' becomes jealous of the 'copy' and the substitute exceeds his functions.

The Sevillano's guest is a story full of intrigues. The title alludes to the fact that a character who appears, the guest of the El Sevillano inn in Toledo, is the writer Miguel de Cervantes.