Because of Friar John's confinement in the house in Verona, he was unable to deliver a message to Romeo at Mantua. The message explained that news of Juliet's death was false, for she had taken a potion to render her insensible for a time, to avoid marriage to Paris. His failure to deliver this information was crucial, for Romeo did indeed hear of her death and, unaware of the circumstances, returned in anguish to Verona. From that point the tragedy unfolded inexorably. Shakespeare's audiences would immediately have understood his device, for plague intermittently disrupted social and commercial intercourse, as it had been doing for almost 250 years.
- From The Great Plague by Stephen Porter