The gang makes--then breaks--a pact to celebrate New Year's Eve without dates. Ross compensates for his loneliness by getting a roommate, a monkey named Marcel.

Phoebe gets upset with Joey when he blows off dinner with her for a date, however only a few days later she finds herself in the same situation but with their roles reversed. Meanwhile, Chandler and Rachel enjoy a cheesecake that gets delivered to their address by accident. They feel guilt-ridden at first, but it's just too delicious. Also, Ross and Monica attend a wedding reception of their cousin and find themselves in an awkward situation.

Ross and Rachel hire a nanny for Emma named Sandy and things seem to be going great. However, Ross is uncomfortable having a male nanny. Meanwhile, Chandler becomes upset when Monica says that somebody from her new job is the funniest guy she's ever met. Also, after Phoebe and Mike decide to take their relationship to a new level and exchange apartment keys, Phoebe gets a surprise visit from her ex-boyfriend David.

Rachel and Phoebe take Joey's girlfriend Charlie shopping, where she overhears the two of them gossiping about Joey. Meanwhile, Ross gives a presentation to a fellow professor in the hopes of getting the role of keynote speaker at the paleontology convention in Barbados. Also, Monica and Chandler consider alternate pregnancy options making some people really uncomfortable in the process.

The gang heads down to Barbados for the paleontology conference. While Ross and Charlie are excited about attending multiple seminars, the rest of the gang just want to enjoy their time on the beach but the rainy weather prevents them from doing so. Things, however, are far from boring - Phoebe discovers that she still has feelings for Mike even though she enjoys spending time with David, Rachel feels lonely and struggles to keep her feelings about Joey to herself, and Chandler is amused by Monica's hair.