Will's father George returns, harboring a spicy secret, in this intrigue-filled episode. As if sitting through "Seussical" on a date with a Frankenstein lookalike weren't rough enough, Grace spies George at the theater—getting very cozy with a woman who isn't Will's mother. After she spills to Will, he goes into denial, refusing to deal with this revelation. But an explosion comes anyway when George's giggly mistress is indiscreet. Meanwhile, Karen and Jack plot to nail Stan, who's also suspected of adultery.