Matt married Sarah on their first date. Ruthie finds out, and Matt swears her to secrecy. Matt carries Sarah into her house, where they are met by her father. He demands he put her down, and reminds them both that Sarah will marry a nice Jewish boy when she turns 30. Sarah says she will tell her parents, and Matt can tell his, but Matt thinks they should both tell so they can start their life together. Sarah decides to make up a worse scenario (that she's pregnant), and then lessen it by telling them the truth, but chickens out, and tells them they are engaged instead. Matt is mad they are starting their relationship with a lie. Sarah wants both sets of parents to be thrilled, so they should wait until they get to know him and the Camdens get to know Sarah. Sarah's mom (who calls Matt Mark) thinks they are married, but her dad is going with engaged. When they go to the Camdens, everyone is waiting for them. Ruthie calls hotels in Glen Oak looking for Matt, who answers the phone, "Mr. and Mrs. Matt Camden's room." She has a hard time keeping the secret that Matt and Sarah are married. Has a hard time keeping the secret, so she confides in Mrs. Riddle that she has a secret, and if she doesn't tell someone soon, she will go crazy. Mrs. Riddle tells her that if it will hurt people, it is sometimes better to not tell.
After finding out about the engagement, Annie and Eric wish they would have gotten married instead. They decide to think that, and are much happier with the whole thing.
Lucy and Mary go after Ruthie when they suspect she knows something about Matt and Sarah. Neither believes they are just engaged. Simon says they probably want to plan a real wedding, and pick out china. Lucy gets teary when she thinks about how she and Jeremy looked at china patterns, and Simon tells her that one day she will meet Mr. Right.
Mary tells Robbie that she often thinks about the two of them being married, even though she knows he loves Joy. She fantasizes that the two of them are married, working their way through school and living with the Camdens until they can afford to move out. Robbie reminds her that he is in love with Joy, and that there is a nice guy out there for her. Like everyone else, they don't believe that Matt and Sarah are just engaged.
Matt and Sarah tell them Camdens they are engaged. Annie welcomes Sarah to the family, and Sarah tells them to get ready for a nice Jewish wedding. Matt says they wanted to get married, and they know everyone thinks they are crazy, but he is in love and wants to marry her. He was lonely in all his other relationships, and now he isn't. He wants the Camdens to respect his decision; it's his life. Matt drops Sarah off at home, and talks to Ruthie about how important it is to keep the secret. Ruthie tells Matt that she loves him, respects him, and will keep the secret for life.