When Carter Pewterschmidt cancels the annual Quahog Christmas carnival, because he hates the holiday, Peter must transform his father-in-law from a Scrooge into a hometown hero in order to salvage the event. Meanwhile, Stewie devises a master plan to get the one and only thing he wants for Christmas.
Stewie and Brian travel back in time to 17th-century Jamestown and make too many close calls with changing history. Stewie decides to destroy his time machine, but comes to regret it when Brian dies after being hit by a car. Devastated by his death, the Griffin family goes out and adopts another dog from the pet store, Vinnie, who is quickly accepted by all the members of the Griffin family, other than Stewie, who can't get over the loss of Brian.
Quagmire dates a woman named Sonja, who is just as sexually active as he is, but things take a turn for the worse when she kidnaps him to be her sex slave, so Peter, Joe and Ida must search the seedy back alleys of Quahog to rescue him. In the meantime, Brian, Stewie and Rupert get involved in a most unusual love triangle.