Weeks was educated at Pembroke College, Oxford, where she read English (graduating with upper-second class honours). She has recently starred in The Five, created by bestselling thriller writer Harlan Coben. She is currently best known for her parts in three television series: Close Relations (1998), Ladies & Their Gentlemen (2002–2006), and Foyle's War (2002–2010, 2013, 2015). In the last, a BAFTA Award–winning detective series set in Hastings during and just after World War II, she starred opp