For a three-act plot analysis, put on your screenwriter’s hat. Moviemakers know the formula well: at the end of Act One, the main character is drawn in completely to a conflict. During Act Two, she is farthest away from her goals. At the end of Act Three, the story is resolved.
Act I
Titus returns to Rome after ten years of war with the Goths, names Saturninus emperor, and sacrifices Tamora's eldest son in a "religious" ritual.
Act II
Tamora, who has just become the Empress of Rome, is ticked off that Titus killed her son. She and her lover, "Aaron the Moor," proceed to brutally torment Titus and his family.
Act III
Titus gets revenge by serving Tamora's sons to her for dinner and then stabbing her to death before he himself is killed. His son, Lucius, becomes Rome's new leader.