At the height of his fame and success—his masterpiece, "The Importance of Being Earnest", was still on stage in London—Wilde sued his lover's father for libel. After a series of trials, Wilde was convicted of gross indecency with other men and sentenced to two years of hard labour in Reading Gaol (jail). In prison he wrote "De Profundis", a long letter which discusses his spiritual journey through his trials, forming a dark counterpoint to his earlier philosophy of pleasure.