Between 1860 and 1861, Ellen Wood (writing as "Mrs. Henry Wood") published her serialized novel East Lynne. The next year stage adaptations of the play began flooding theatres, creating one of the dramatic sensations of the latter nineteenth century.
Though the novel takes place in England, the first stage adaptation was actually in the U.S., premiering at the Brooklyn Academy of Music on January 26, 1862. The adaptation was anonymous, and it closely followed both the plot and the language of the original.
The story surrounds Lady Isabel, an earl's daughter who marries the rising lawyer Archibald Carlyle. Isabel grows jealous, suspecting her husband is in love with another woman, Barbara Hare.
The play weaves together this jealousy plot with a murder mystery. Barbara's brother Richard must stay in hiding because he has been falsely accused of murder. He suspects the real killer to be a man he knows only as Thorn.
In the second act, Isabel sees her husband arm in arm with Barbara Hare, not realizing Archibald is actually trying to help exonerate her brother. Her jealousy becomes so intense, that she agrees to run off with a scoundrel named Sir Francis Levison just to revenge herself on her husband. She regrets her decision in the very next act, though, sending Levison away and refusing to take money from him or from her own relatives.
Typically, the climax of a melodrama was in the fourth act. This is where Isabel disguises herself as "Madame Vine" to get a position caring for her own children. We have to suspend disbelief to accept that Archibald doesn't recognize his own wife, but the dramatic payoff is worth it. Isabel is forced to watch her own sickly son slowly die, but is unable to tell him she is his mother. Many adaptations had her utter something along the lines of: "Dead! And never called me mother." That line doesn't appear in the book, though, nor is it in the first stage adaptation.
The fifth act wraps up the action, with Richard Hare being cleared of the charges against him, and Levison (who was actually the mysterious "Thorn") being convicted of murder. Isabel, of course, has already been tainted, so she ends up dying amid tears of repentance.