¿Por qué pecamos a los 40? (1970)
Alejandro Quesada (Fernando Fernán Gómez), un eminente médico cuarentón con gran éxito entre las mujeres, impulsa a sus antiguos amigos Federico (Juanjo Menéndez) y Enrique (José Luis López Vázquez) a cambiar su actitud ante la vida. La muerte de otro amigo común, Luis (Jesús Puente), los reafirma en el intento de disfrutar de su existencia y buscar la relación con mujeres de menor edad que sus esposas.
Directora: Pedro Lazaga Sabater
| Directing | Pedro Lazaga Sabater | Director |
| Costume & Make-Up | Amalia Sánchez | Costume Design |
| Writing | Pedro Masó | Writer |
| Sound | Pedro Masó | Dialogue Editor |
| Camera | Juan Mariné | Director of Photography |
| Camera | José Salvador | Director of Photography |
| Sound | Arturo García | Sound Recordist |
| Costume & Make-Up | María de Elena | Makeup Artist |
| Production | Jaime Gallart | Production Manager |
| Directing | Isabel Ruiz Capillas | Script Supervisor |
| Production | Leandro Iglesias | Production Assistant |
| Editing | Alfonso Santacana | Editor |
| Sound | Rogelio Armada | Sound Recordist |
| Production | Ángel Masó | Production Assistant |
| Costume & Make-Up | María Teresa Iglesias | Costume Design |
| Art | Amalia Sánchez | Production Design |
| Lighting | Juan M. García | Lighting Manager |
| Writing | Antonio Vich | Writer |
| Art | León Revuelta | Production Design |
| Production | José Alted | Unit Production Manager |
| Camera | Miguel Agudo | Director of Photography |
| Art | Carlos Orengo | Property Master |
| Sound | Jaime Torrens | Sound |
| Sound | Antón García Abril | Music |
| Directing | José Luis Pérez Tristán | Assistant Director |
| Production | Pedro Masó | Producer |
| Camera | Luis Berraquero | Director of Photography |
| Costume & Make-Up | Tomasa Benito | Assistant Makeup Artist |
| Costume & Make-Up | Consuelo Zahonero | Hairstylist |
