After learning that they are going to be grandparents, the Flintstones and the Rubbles head for Hollyrock to visit their kids. Pebbles is busy with her advertising career, while Bamm-Bamm is trying desperately to sell his screenplay -- and neither is prepared to deal with a month-long visit from their overbearing parents. As Wilma and Betty take over preparations for the baby, Fred and Barney set out to sell Bamm-Bamm's screenplay -- against his wishes. Trying to peddle the screenplay, Fred stalks actress Shelly Millstone and inadvertently gets his bowling ball switched with a giant stolen pearl, inciting the wrath of a crime boss. Meanwhile, Pebbles and Bamm-Bamm are frustrated with their mothers' taking control of everything.