The devilishly named Satan's Whiskers cocktail is a longstanding classic, catalogued in the Savoy Cocktail Book (1930) and likely of even older vintage. It's a "perfect" drink, meaning that it contains equals parts of sweet and dry vermouth. The base spirit is gin, and many versions of the recipe call for orange liqueur, orange juice, and orange bitters, resulting in a rounded, layered exploration of the citrus fruit in all its bitter-juicy-sweet complexity.
Those who've researched the history of the Satan's Whiskers, such as writer Ted Haigh (the drink is documented in his book Vintage Spirits and Forgotten Cocktails), tell us that mixing it with Grand Marnier, the robust, cognac-based orange liqueur, makes for "straight" Whiskers, while using drier orange curaçao instead yields a "curled" one.
The Satan's Whiskers Cocktail
1 ounce gin
1/2 ounce sweet vermouth
1/2 ounce dry vermouth
1/2 ounce orange liqueur (try Grand Marnier or orange curaçao)
1 ounce fresh-squeezed orange juice
1 dash orange bitters
Combine the ingredients in a Boston shaker or cocktail shaker. Add ice and shake vigorously for 10 seconds. Strain the contents into a chilled cocktail glass.