The Mystery Play is a dramatic form that has been passed down through the ages. It differs from other plays by showing on stage the connection between the spiritual world and the earth; it reveals the activity of the spiritual beings who work from the heavens to help or hinder human beings in their earthly lives. For the classical Greek playwrights, such as Aeschylus, the involvement in daily human life of divine forces, personified in the Gods and the Furies, was a reality that they allowed to appear onstage. In a more modern era, the most famous Mystery Plays are perhaps those of the York Cycle, a series of at least 48 plays, performed by the York Craft Guilds from 1376 to 1569. In the year 2000, a revival of the York Cycle was staged in the York Minster as The York Millennium Mystery Plays.