This chapter traces the fortunes of Aaron Hill’s English translation (1735) of Voltaire’s tragedy Zaïre (1732), from its first performance under Hill’s direction outside the patent theatres to David Garrick’s reworking of it at Drury Lane. I show that Zara’s scepticism of established religion and her father’s deathbed proselytising are used by Hill to produce what his friend John Dennis called an ‘enthusiastic’ passion and suggest that Voltaire’s work appealed to Hill for its handling of religious material capable of producing extreme sequences of sublime emotions. At the same time, Hill’s Zara is also an exposition of what Hill described as ‘dramatic passions’. Those who read, saw, or performed Zara could witness the outward marks of many passions and trace on stage and on the page their performance through transition to the very instant. Such opportunities made the play perfect for what Hill called an ‘Experiment’ on English tastes and acting. When Garrick came to revive this experiment in the 1750s, its passions become the property of Garrick himself, as he rewrote sections of the play to favour his character of Lusignan.