In March 2016, Cleo had become involved in the car accident with Holly, Nathan Nightingale (Jared Garfield) and Nathan's fiancee Rachel Hardy (Jennifer Brooke) after Holly hit the car following getting herself drunk where Nathan and Rachel had been.
On 24 June 2016, whilst at her court case against Pete, Cleo reveals that Holly was the one driving the car that hit into Nathan's car and caused the explosion that killed Rachel.