Duckman and Cornfed in 'Haunted Society Plumbers' - S4.E14

Duckman and Cornfed become plumbers and their first job takes them to a society gathering in a mansion. While not doing his job, Duckman discovers that the cursed ""Sharon Stone"" is missing; he and Cornfed try to recover the diamond before the hostess discovers the theft. After the diamond is revealed to be missing, its curse comes into play and traps them in the mansion.