In 2010, Lock was cast as the main character in the CBBC television show Sadie J,[4] which ran for three series from 2011 to 2013. In addition to playing the lead, she recorded the theme song, "In A Boy's World". The theme tune was officially released by Demon Records, in association with the BBC. A shortened version of the song is used for the Sadie J title sequence.
In April 2014 it was announced that Lock had been cast as Bella in the Disney miniseries Evermoor alongside Naomi Sequeira, Jordan Loughran, George Sear and Georgie Farmer.[5][6] In March 2015 it was announced that the miniseries had been given a full series order under the working title of The Evermoor Chronicles,[7] with Lock set to reprise her role as Bella.[8]
In April 2015 it was announced that Lock would co-present Michel Roux Jr's upcoming Disney reality children's cooking competition First Class Chefs alongside Evermoor co-star Finney Cassidy.[9][10]
In October 2020, Lock published a poetry book titled, With Every Wave.[11]