Millie Bobby Brown just switched up her hair again, debuting her darkest color yet. The Stranger Things star debuted a bold new 'do at the 2025 Miami Open on Thursday, March 27, while attending the women's semifinals with her husband,

Consult your colourist: The first step to any hair makeover is to book a consultation with a trusted colourist. In other words, put that at-home box dye down!! If you're transitioning from dark hair to blonde, this process may take a few sessions, depending on the health of your hair and the shade you're aiming for.