H6: Diary of a Serial Killer is a 2006 Spanish horror film directed by Martín Garrido Barón and was written by Martín Garrido.^[1]

H6 tells the story of Antonio Frau, a serial killer set free after serving 25 years in jail for the violent murder of his girlfriend. After inheriting an old motel from a relative he never knew, he sees this as a signal and takes to his holy task of relieving the grief of those who have lost the will to live. He takes his victims to room Number 6 in the motel where he 'purifies' them, while, at the same time, continues his everyday life next to his wife. A mistake leads to his arrest, and his plan to become rich and famous takes relevance.

• Fernando Acaso as Antonio Frau
• Ángel Alarcón as Francisca's Father
• Raquel Arenas as Rosa
• Ruperto Ares as Pablo
• María José Bausá as Francisca
• Ramón Del Pomar as Curro
• Miquel Fernandez as Antonio Frau
• Martín Garrido as Miguel Oliver
• Antonio Mayans as Dr. Planas
• Sonia Moreno as Tina
• Xènia Reguant as Marisa
• Mark San Juan as Peralta
• Alejo Sauras as Cristóbal
• Elena Seguí as Soledad Mendez
• Miquel Sitjar as Flores

The film premiered on 29 April 2005 as part of the Málaga Film Festival.^[2] It was on 3 November 2005 part of the San Sebastián Horror and Fantasy Film Festival and the renovated Festival de Cine Negro de Manresa on 19 November 2005.^[3] H6 had a theatrical release in Spain on 7 July 2006 and was in the United States released as direct to video production on 21 November 2006.^[4]