Parties involved in the 1925 Scopes Trial

William Jennings Bryan, known as the great commoner, emerged from semi-retirement to assist in the prosecution of John Scopes, accused of heresy. Bryan prepared for the trial with much publicity. Meanwhile, Scopes was supported by renowned attorneys Clarence Darrow and Dudley Field Malone, who accepted the challenge to defend him in Dayton.

What was the context in which Bryan prepared his brief?

Describe the role of Scopes in the trial mentioned in the text.