What? A striking, strapless ball gown in hot pink, paired with her signature blonde curls, smoky eye makeup and a matching cerise lip colour for a performance in Selfridges. The disco ball-esque walls and the sparkling microphone added an extra helping of glamour to Katherine's perfect prom queen look.
Where? Selfridges, London, 11 July
Verdict? Let us know how you rate KJ's latest look in a comment and see more from the singer in her style evolution below:
Hear from Katherine in an interview after singing for the Queen in the video below: