Film director Ken Loach has criticised the current crop of TV period dramas for indulging in "fake nostalgia".
In response to a question about Downton Abbey in a Radio Times interview, Loach said: "This rosy vision of the past, it's a choice broadcasters make.
"'Don't bother your heads with what's going on now, just wallow in fake nostalgia'. It's bad history, bad drama. It puts your brain to sleep."
Period dramas such as Victoria and Poldark have been a ratings success.
Other hit series include ITV's Downton Abbey and Mr Selfridge and the BBC's Call the Midwife and War and Peace.
Loach said nostalgic dramas were "the opposite of what a good broadcaster should do, which is stimulate and invigorate".
The filmmaker also said broadcasters should "diversify" so regions could create their own dramas.
"The directors I know in television say it's a nightmare. That's true for all the broadcasters, but the BBC is a rotten place for a director."
The BBC said in a statement: "The quality, range and ambition of BBC Drama is evidence of an organisation in top creative form that supports both the director's voice and reflects the whole of the UK.
"From world-class British directors like Peter Kosminsky redefining period drama with Wolf Hall, or Julian Farino's Bafta-winning Marvellous, visionary directors have a home on the BBC and this means we also attract directors from across the world like the Emmy-winning Susanne Bier on The Night Manager to Oscar winner Jane Campion.
"BBC Drama is produced across the nations and regions of the UK from Happy Valley to Peaky Blinders, The Fall, Shetland, Poldark, The A Word, Last Tango in Halifax and Ordinary Lies."
Loach also took aim at the BBC over its news output.
"Its notion of news has got to be challenged. The BBC is very aware of its role in shaping people's consciousness... it's manipulative and deeply political," he added.
The BBC said: "BBC News is independent and adheres to clear published editorial guidelines including on impartiality. The BBC is consistently rated the most trusted and accurate news provider by the majority of people in the UK."
Loach's latest film I, Daniel Blake, which was co-produced with BBC Films, won the Palme d'Or at Cannes Film Festival earlier this year.
His other films include Kes, Land and Freedom, My Name is Joe and Sweet Sixteen.
Loach's breakthrough came with his 1966 BBC landmark play Cathy Come Home, which tackled the issue of homelessness.