Mary returns home back to Glenoak for the summer to spend some time with her family, but fears about being together again with Robbie. Eric and Annie are recipients of what may or may not be advances from unmarried acquaintances. Simon and Deena see that they still have feelings for each other, even though she has a boyfriend. Matt agonizes over telling his family about his new relationship with Cheryl, but soon decides to tell them all. Lastly, Lucy surprises herself and others when making a proposal to Jeremy and the possibility of going to college in New York with Jeremy. Although plans change when Mary, feeling rejected by Robbie, makes a shocking declaration.

Mary tries to right a wrong by explaining to Lucy that she never had adult relations with her sister's fiance. The only problem left is trying to convince Lucy. Wilson unexpectedly drops by the Camden home from New York to see if he and Mary are really over by finding out her answer. James talks to Eric about him attempting to have an affair with Annie as Serena comes clean with Annie about her trying to have an affair with Eric. Robbie and Wilson set aside their differences so that they can talk about Mary. Matt learns a few things when it comes to Cheryl's honesty when she doesn't tell her friends that she's dating him.