This drink's moniker refers to one of the original actors in the play Arsenic and Old Lace, in which two sisters murder a series of men with poisoned elderberry wine.
Pinch each of finely grated lime zest and freshly ground pepper, for garnish
In a cocktail shaker, combine the gin, elderflower liqueur, lime juice, sugar and egg white. Shake well. Add ice and shake again. Strain into an ice-filled collins glass, stir in the club soda and garnish with the lime zest and pepper.