Louis Theroux is to present a new documentary series looking into the "extreme" side of life in Los Angeles.

The TV presenter spent a year living in the city to make the three films which will air on BBC Two later this year.

The documentaries will look at the treatment of patients with terminal illness at Hollywood's Cedars-Sinai Medical Centre, sex offenders after they are released from prison, and the way the city deals with neglected and feral dogs.

Louis said: "I've been living in Los Angeles with my family for the past year or so. It seemed a chance to explore different sides of a single place, by spending longer immersed in stories and going deeper with the subjects.

"I have a love-hate relationship with the city. It embodies the best and worst of America. It combines wealth and glamour with social breakdown and deep neglect. We've concentrated on stories that take us into the extremes of life and the extreme parts of one of the world's great cities."

The three films will air on BBC Two in the spring and continue the documentary maker's examination of American life since his When Louis Met ... series came to an end in 2002, featuring Max Clifford, Neil and Christine Hamilton, and the late Jimmy Savile.

His past films made in the US have focused on neo-Nazis, the US prison system and The Most Hated Family in America, about a family at the Westboro Baptist Church. Louis has also dealt with the subject of "extreme love", investigating the effects of autism and dementia.