She has had television roles in The Crown (playing Wallis Simpson), in May 33rd (2004) for which she was nominated for a BAFTA, and in The Missing (2016), Kiri (2016), His Dark Materials (2019–2022) and The Capture (2019–2021).
[4] In 1997, Williams appeared opposite Michael Gambon in London's West End and on Broadway in David Hare's Skylight,[4] (Olivier and Tony Award nominations).
[4][5] Other leading theatre performances include Rosalind in As You Like It for the RSC,[5] Alan Ayckbourn's Absurd Person Singular, Henryk Ibsen's The Lady from the Sea,[5] and Pinter's Old Times, in which she alternated the roles of Anna and Kate with Kristin Scott Thomas.
[2] Subsequent film appearances have included supporting roles in Firelight (1997),[6] Shot Through the Heart (1998),[6] The King Is Alive (2000),[6] Girl from Rio (2001), and The Christmas Miracle of Jonathan Toomey (2007).
[7] In 2021, Williams directed an acclaimed production of Doubt by John Patrick Shanley at Chichester Festival Theatre, West Sussex.
[citation needed] She has been in a relationship with the actor Angus Wright since 2015; they first met after starring together in a production of the Oresteia at the Almeida Theatre.