Armstrong's first documentary, McLibel (1997, 2005), told the inside story of the infamous McDonald's libel trial. Filmed over ten years with no commission, no budget and a voluntary crew - including Ken Loach, who directed the courtroom reconstructions - it shot to notoriety after getting stopped by lawyers at first BBC1 and then Channel 4 on its first release in 1997.
Eight years later - after the 'McLibel Two' had defeated the British government at the European Court of Human Rights - it was finally broadcast on BBC2 to excellent viewing figures (1 million at 10.30 pm on Sunday), and fantastic reviews.[citation needed] It was then broadcast on TV in 15 countries - including Australia, Canada and America - and released on DVD worldwide. Cinema Libre distributors released McLibel in American cinemas and DVD stores in summer 2005 and Revelation followed in the UK in 2006. McLibel was nominated for numerous awards, including the Grierson Documentary Award and the British Independent Film Awards. It was recently picked for the British Film Institute's prestigious series, "Ten Documentaries which changed the World".
Armstrong's second feature documentary, Drowned Out (2002), follows an Indian family who chose to stay at home and drown rather than make way for the Narmada Dam. It also sold around the world, was nominated for Best Documentary at the British Independent Film Awards 2004 and was released theatrically in America and DVD worldwide in 2006.