California Governor Arnold Schwarzenegger greeted his Twins (1988) costar Danny DeVito on a location set to congratulate him on his efforts to produce the film in California, rather than succumb to the tax lures and lower labor costs offered by other states. DeVito acknowledged that he had to persuade the film's cast and crew to take pay cuts in order to offset the lower production costs that other states offered. They're "working for much less than they normally work for".
Both Danny DeVito and Ed Begley Jr. had roles in Batman movies. Danny DeVito played The Penguin in 'Batman Returns'. Ed Begley Jr. played Mr. Stickley, The Riddler's supervisor in 'Batman Forever'.
Michael McKean and Martin Mull both starred in Clue (1985).
During the charades scene, Kathy Bates' character mentions actor Richard Gere and makes a vulgar noise implying she finds him attractive. Christine Baranski's character then gives an appalled reaction. Baranski and Gere had costarred in "Chicago" (2002).