Martin struggles to act normally when Sonia introduces him to a smug Sarah. When Sonia leaves the room, Martin urges Sarah to leave but she refuses, upset that Martin has not told Sonia about her. The tension in the room rises when Sarah confides to Sonia that she is depressed because she is waiting for her married boyfriend to get divorced. Martin is convinced that Sarah is mad and tells her so when they're left alone. Sarah, however, has an ultimatum: he can tell Sonia or she will. (thetvdb.com)