Shani Darden is an LA-based aesthetician loved by celebrities like Emily Ratajkowksi, Rosie Huntington-Whitely, and Jessica Alban, and her Shani Darden Retinol Reform (£80) is a favourite amongst top beauty editors for the fact the formula is so incredibly gentle. It also comes recommended by dermatologist Dr Adeline Kikam, who added it to her list of "Top OTC Retinoids" on her Instagram account @brownskinderm.
The formula contains 2.2% encapsulated retinol ester, along with lactic acid, an exfoliating alpha hydroxy acid that also acts as a humectant, which helps to pull moisture into the skin. Using this serum on a regular basis (starting twice a week and working your way up to more), and your complexion is left smoother, brighter, and clearer.