"These typically lighten up to five shades, so if you are a medium brown color, they can take you to a soft golden blonde. Or if you have dark hair naturally, they will lift to a nice caramel ...

This is perhaps why Bleach London’s range of at-home products is so comprehensively thought-out when it comes to formulations. This includes its latest launch, which might just be its smartest to date ...

Luckily, my many bleach and dye escapades ... overpromise,” she says. “My color lasted for months, and my hair looked great after each wash.” Olaplex No. 4 is a bond-building product.