Malcolm in the Middle (2000)

S6E18 Ida's Dance

Lois pays a visit to Ida, only to be taken aback by the chaotic St. Grotus Day festivities. Meanwhile, Malcolm struggles with a music appreciation class and reluctantly seeks Dewey's assistance. In another corner of the house, Reese and Hal sneak in some horror films while Lois is out, but their movie night uncovers surprising truths about both of them.