She was also in the main cast of the medical drama Holby City for three series playing Chloe Godard.
[1] Lennox played Margot in the original West End cast of Legally Blonde in 2009, for which she also understudied Sheridan Smith in the leading role of Elle Woods.
[2] In 2011, Lennox performed in the play Decade directed by Rupert Goold for Headlong Theatre, the 12 person cast also included Tobias Menzies.
In 2015, she played Cathy Hiatt in The Last Five Years at Lyric Theatre in Belfast alongside the actor Fra Fee.
On 21 March 2022, she took over the role of Sally Bowles in Cabaret at the Playhouse Theatre, starring alongside Fra Fee.