When a severe flu outbreak sweeps Philadelphia the gang voluntarily quarantine themselves inside of Paddy's in an attempt to keep their singing voices pristine for an upcoming competition, although they have trouble adhering to the strict rules they've set for themselves.

After creative differences over what constitutes tasteful nudity cause Frank to pull his money out of Lethal Weapon 6 during filming, Mac, Dennis, and Charlie screen their rough footage for investors in hopes of raising enough capital to finish the production of their latest masterpiece.