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
Say hello to Elesin Oba, the king's horseman. Following Yoruban tradition, Elesin is supposed to sacrifice himself and follow his king into the afterlife—the play opens on the day that Elesin is supposed to complete this mission. His peeps (Iyaloja and the Praise-Singer) seem a little concerned that he won't be able or willing to pull off the ritual, but Elesin is not worried in the least. Or so he says. As part of his efforts to enjoy his last day on earth, he asks Iyaloja to arrange a marriage with an attractive young girl he sees walking by.
Act II
Meanwhile, the British authorities in the area are not keen on the idea of allowing a ritual suicide to take place on their watch, especially with the British Prince in town. So Simon Pilkings, the local District Officer, sends word to the local police to stop Elesin. However, this proves easier said than done, and Simon ends up having to leave a ball that evening to intervene himself. While he's out doing so, Olunde, Elesin's son, arrives and talks cultural difference with Jane.
Act III
Simon is successful in his quest to prevent Elesin from committing suicide, and Elesin is arrested and thrown in prison. Iyaloja visits and reprimands Elesin for his weakness in not getting to the other side before he could be stopped—and then she reveals that Olunde has sacrificed himself to help right the wrong Elesin committed by failing in his duty. Seeing his son's dead body, Elesin promptly strangles himself before anyone can stop him.