The Rehearsal was a satirical play aimed specifically at John Dryden and generally at the sententious and overly ambitious theater of the Restoration tragedy. The play was staged in 1671 and published anonymously in 1672, but it is certainly by George Villiers, 2nd Duke of Buckingham and others. Several people, including Samuel Butler of Hudibras fame, have been suggested as collaborators.
The play concerns a playwright named Bayes attempting to stage a play. The play he is going to put on is made up almost entirely of excerpts of existing heroic dramas. The name "Bayes" indicates the poet laureate. The previous poet laureate had been William D'Avenant, and D'Avenant did stage spectacles and plays with exceptionally bombastic speeches from the heroes (e.g. The Siege of Rhodes). However, the poet laureate at the time of the play was Dryden, and most of the excerpts in the play-within-a-play are liftings from Dryden. In particular, Dryden's The Conquest of Granada, which had been his most popular play (and the one whose preface had defined "heroic drama"), is the play Buckingham parodies. Dryden had written other heroic drama aside from The Conquest of Granada. In fact, he had been so prolific in that vein that Martin Clifford accused him of "stealing from himself." The reason that The Conquest of Granada was such a target, however, is the Preface to the printed version of The Conquest of Granada. There, Dryden scolds his fellow dramatists for having immoral heroes and low sentiments, and he proposes a new type of theater, the heroic drama. Buckingham's play is, in a sense, the old theater biting him back. In The Rehearsal, a director/author attempts to put on a new play, and he lectures his actors and critics with impossible and absurd instructions on the importance of what they are doing.
The Rehearsal infuriated Dryden, and it is not possible to see the satire without some political cause or effect. (Dryden would not forget the satire, and he made Buckingham into the figure of Zimri in his Absalom and Achitophel.) However, for readers and viewers what was most delightful was the way that Buckingham effectively punctures the puffed up bombast of Dryden's plays. By taking Dryden's own words out of context and pasting them together, Buckingham disrupts whatever emotions that might have gone with them originally and exposes their inherent absurdity.
The play is credited with putting an end to heroic drama, but, in the long run, it did not. If "heroic drama" is understood only as the writings of Dryden in an heroic vein, then perhaps The Rehearsal was a success. Dryden was unable or unwilling to pursue heroic drama for long after The Rehearsal came out. Whether The Rehearsal or the she-tragedy made popular by the acting of Elizabeth Barry did it, there was a turn away from the Classical heroes of Dryden's heroic drama. However, new plays with exaggerated heroes who mouth impossibly high-sounding moral sentiments and accomplish impossibly extravagant actions continued to be written through to the 1740's (see, for example, Henry Carey's Chrononhotonthologos). In fact, the trend toward absurdly lofty bombast and sentiment was so strong that Richard Brinsley Sheridan reworked The Rehearsal for his play, The Critic (1779), where the target was the inflated importance and prose of theater criticism. To some degree, the parodic form of a play-within-a-play goes back to Shakespeare's satire of pantomime plays in A Midsummer Night's Dream and forward to the contemporary Mel Brooks play, The Producers.