Jimmy Fallon had a running gag on “The Tonight Show” Friday (July 25) that culminated in Jon Hamm being attacked by a fake door-to-door crack dealer, but to fully appreciate the joke, you must start at the beginning of the night.

Above, Fallon’s monologue features a joke about a man who got fired from McDonald’s for dealing crack on the job. The joke snowballs into someone trying to get you to add crack to your order at a McDonald’s drive-thru and ends with the aforementioned door-to-door crack salesman — watch the videos in order, it’s worth it.

And in case you missed it, later Hamm and Fallon took part in a rather amazing sketch about the TV show they did together in the 1980s called “Palisades Park Pet Patrol.”