Guest Stars James Michael Tyler as Gunther Giovanni Ribisi as Frank Buffay Jr. Paget Brewster as Kathy Debra Jo Rupp as Alice Knight Teri Garr as Phoebe Sr. Sherri Shepherd as Rhonda, The Tour Guide Jim Bentley as Another Tour Guide Miles Marsico as The Smart Kid Chip Chinery as Another Scientist Jack Ong as The Older Scientist