The Spam Fantastic

I just read yesterday about the phenomenon of "empty" spam: spam that contains large chunks of literature (generally of the 18th-century variety) to slip past filters. Lo and behold, today it happens to me! In a solicitation for Mr. Clean's Magic Erasers, I received the synopsis of what seems to be a blood-and-guts Spanish tragedy. Anyone want to hazard a guess as to what play this could be?

Act I, Scene i Don Andrea, a Spanish courtier, has been killed in battle against the Portuguese. His soul is brought out of oblivion by Revenge to witness the death of his killer, Balthazar, at the hands of his lover, Bel-Imperia. Act I, Scene ii A Spanish General describes the battle, in which the Spaniards were victorious, to the King of Spain. Lorenzo and Horatio bring Balthazar as a captive before the King who says that he shall be treated with honour. There is debate between Lorenzo and Horatio as to who took Balthazar captive. The King decrees that Lorenzo shall have Balthazar's weapons and horse, and that Horatio shall have the ransom. He places Balthazar in Lorenzo's charge. Balthazar asks Horatio to keep him company. Act I, Scene iii The Portuguese Viceroy learns that Balthazar has not been killed in the battle, but taken prisoner. Villuppo claims that Alexandro tried to kill Balthazar which caused the Portuguese rout. The Viceroy has Alexandro led away, while Villuppo hopes to benefit through his deception. Act I, Scene iv Horatio tells Bel-Imperia about Andrea's death. Bel-Imperia transfers her affections to Horatio and have her revenge on Balthazar. Lorenzo and Balthazar come across her. Balthazar is in love with Bel-Imperia and there is witty, but pointed by-play between them. Bel-Imperia drops her glove which is retrieved by Horatio who reports that the King and Portuguese Ambassador are coming. Hieronimo, Horatio's father, arrives with a dumb-show which he explains as England triumphing over Spain. The Ambassador interprets this as a warning to the King for Spain not to be too proud after the victory. Act I, Scene v Andrea complains that all he has seen is Balthazar having a good time. Revenge assures him that it will not last.
...Act IV, Scene i Bel-Imperia claims that Hieronimo is not doing anything to avenge Horatio. He already has a plan in mind. Lorenzo and Balthazar enter. As one of the entertainments for the wedding, Hieronimo intends for them to act in a play about Erasto, the Knight of Rhodes, with each of them taking a part, and each speaking a different language. Act IV, Scene ii A distraught Isabella enters. She kills herself. Act IV, Scene iii A brief scene in which Hieronimo is preparing for the play. Act IV, Scene iv The play is acted before the King and Viceroy. In the guise of the Turkish emperor's lieutenant, Hieronimo stabs Lorenzo who is playing Erasto the Knight of Rhodes. Bel-Imperia, as Perseda, stabs Balthazar (the Turkish emperor) and then herself. Hieronimo reveals the truth and tries to kill himself, but is arrested. The King threatens to torture Hieronimo into telling him who his co-conspirators were, but Hieronimo bites out his own tongue. He then stabs the Duke of Castile and kills himself. Act IV, Scene v Andrea is now satisfied and the dead are all given their just rewards. Lorenzo, Balthazar, Pedringano and Serberine will all be punished suitably, as will the Duke of Castile.

Pretty lurid stuff! An honorable mention goes to the reader who does my Google work for me.

AND the Honorable Mention goes to: both A Philosopher and Bernard Brandt, who inform me that this is none other than Thomas Kyd's A Spanish Tragedy (seems I wasn't far off in my guess!). I've shortened the synopsis accordingly.