In 2014, Williams was cast in the role of Lydia in the British melodramatic coming of age mystery film drama "The Falling", set in an all-girls school, for which she was awarded the London Film Critics' Circle Award for Young Performer of the Year, Evening Standard British Film Award Rising Star and the European Shooting Stars Award at the 65th Berlin International Film Festival for her role in Carol Morley’s feature. The film premiered at the BFI London Film Festival on 11 October 2014 and was released theatrically on 24 April 2015 in the UK. Guy Lodge of "Variety" described Williams as "prodigiously gifted" and giving a "brilliantly articulated ... bristling, often spikily funny performance."