She is known for her roles as Jane Cobden in the BBC series Ripper Street, Celia Donnelly in Fortitude, and the titular role of 'The Woman In Black' in the 2014 film The Woman in Black 2: Angel of Death. Between 2004 and 2014 she had numerous roles in episodes of UK television series such as Casualty, Doctors, Shetland, New Tricks, Line of Duty and as Teresa Fenchurch in Home Fires. Best also appeared as Min Sakul in the sequel Star Wars: The Force Awakens (2015).