As classic as the little black dress, red lipstick has been described as the, "stiletto heel of make-up". In other words, it's instant sexiness - a slick of glamour in a bullet. Voluptuous, velvety, carmine or vermilion, it's been a powerful weapon used by women and men since Egyptian times. Throughout history, women have used red lipstick not only to seduce but as a powerful tool communicate their strength and independence. The Suffragettes wore it in defiance and during the Second World War, women wore it for victory when makeup companies created patriotic packaging creating lipstick shades such as "regimental red" or "lips in uniform". In this special feature for Valentine's Day, Cathy Macdonald speaks to historians and makeup artists to discover the enduring allure of a slick of red lippie.