Add gin, crème de violette, maraschino liqueur, elderflower liqueur, and grapefruit juice.
Shake for 10–12 seconds until well chilled.
Strain into a chilled coupe or highball glass.
Top with club soda and stir gently with a bar spoon.
Garnish with a grapefruit twist or violet flower.
Notes
Serve immediately while cold for the brightest flavor. Swap club soda for dry sparkling wine for a Violette Royale variation. Using quality gin and fresh grapefruit juice makes a noticeable difference.