"The Assembled Parties" welcomes us to the world of the Bascovs, an Upper West Side Jewish family in 1980. In a sprawling Central Park West apartment, former movie star Julie Bascov and her sister-in-law Faye bring their families together for their traditional holiday dinner. But tonight, things are not usual. A house guest has joined the festivities for the first time and he unwittingly -- or perhaps by design -- insinuates himself into the family drama. Twenty years later, as 2001 approaches, the Bascovs’ seemingly picture-perfect life may be about to crumble.