Caroline's romance is beached when Joe's ex returns from an environmental mission.

Del hopes to spark up romance with Annie's neurotic friend Cassandra, who plans on lighting a fire of her own - she's a compulsive pyromaniac just of an institution. Meanwhile, Caroline spends a night out on the town ""alone,"" crashing the restaurant where Richard is trying to enjoy a quiet meal and ultimately being forced by him to attend a movie on her own. Meanwhile, Charlie keeps spotting monkeys throughout Manhattan, and becomes convinced they are taking over the city.

Caroline's date reads more like a Shakespearean tragedy after she tells a lie to James, an attractive novelist she runs into during her book signing, and must then desperately cover for the fact that she hasn't actually read his novel; Richard tables his own remedy when Julia's job at Remo's is a disaster and he has to replace her as waiter; it's bad fortune for Annie when a fortune cookie leads Charlie to believe they share a recipe for love; and Del inadvertently becomes third party on a honeymoon.

Julia throws a surprise birthday party for Richard by inviting everyone in his address book, under the impression that they are his friends, which results in a gathering chiefly of his ex-therapists - one of whom is interested in Annie, to Richard's horror. Meanwhile, the discovery that she has been getting illegal free cable for years puts Caroline in a moral spin, since the rest of the building is hooked into her outlet and anxious for her not to do the right thing.