Hay alguien ahí

The drivers of the story are the Pardo, a bourgeois family.[1] Undergoing a marriage crisis, the parents of the family decide to move with their children into a new house located in an apparently ideal residential area, "La Roseta".[2] Yet both the house and the residential area turned to be the settings for their nightmares.[3]

• Eduard Farelo as Diego Pardo,[4] the father of the Pardo family, a pilot.[5]
• Sonia Castelo as Clara Simón,[4] the mother of the Pardo family, co-owner of an antique shop.[5]
• María Cotiello as Irene Pardo,[4] the elder daughter of the Pardo family; she studies Fine Arts.[5]
• Guillermo Barrientos as Íñigo Pardo,[4] the son of the Pardo family; he studies Business Sciences.[5]
• Mónica Rodríguez as Ana Pardo,[4] the youngest member of the Pardo family; she has an "invisible friend".[6]
• Marina Salas as Silvia Latiegui, Íñigo's girlfriend.[7]
• William Miller as Jorge Selvas, a medium.[8]
• Agnes Kiraly as Nikoletta Blaskó, servant working for the Pardo Simón family.[9]
• Esmeralda Moya as Amanda Ríos.[10]
• Chisco Amado as Luis Latiegui, Silvia's father.[5]
• Bárbara de Lema as Nieves Bruc,[10] Silvia's mother.[5]
• Jordi Dauder as Celestino Poveda.[5]
• Mercedes Sampietro as Begoña García-Inés, Diego's mother.[5]
• Montse Mostaza as Rebeca Santos, Diego's work colleague.[5]
• Carlos Bardem as Justo.[5]
• Velilla Valbuena as Marta Simón, Clara's sister.[5]
• Laura Aparicio as Ruth Berlín, police inspector.[5]
• José Ángel Egido as Profesor Sánchez Albo, professor of psychology, expert in hypnosis.[5]
• Jesús Castejón as Padre Palazuelos, spiritual advisor to Begoña.[5]
• Jan Cornet as Fausto Ladera, Silvia's friend.[5]

Produced by Plural Entertainment, the series was created by Joaquín Górriz, D. C. Torallas and Miguel Ángel Fernández.[4][11] Shooting took place in Villafranca del Castillo.[12] The first season, consisting of 13 episodes,[13] premiered on 16 March 2009.[14] The last episode of the season aired on 8 June 2009.[15] The second season began airing on 19 January 2010.[16] After 2 seasons and 26 episodes, the broadcasting run ended on 9 April 2010.[17]