Cindy Lou Who and her adopted sis, Sister Who are sleeping peacefully as the Grinch sneaks in to steal their Christmas presents. The noise from the Grinch wakes the sisters, who think it might be Santa. They race from their beds, still in their sexy nightgowns, only to come face to face with the Grinch. They run to wake their stepbrother, Brother Who. Brother is very upset to learn that the Grinch has ruined Christmas once again. Cindy Lou is distraught that her brother's upset, but she comes up with an idea to help save Christmas for all of them. Turning to Sister, Cindy Lou tugs her jammies open to reveal her lingerie. Sister gets the hint and does the same to
Cindy Lou, and then both girls advance on Brother to spread some Christmas cheer.