A man in round spectacles dangles from the hands of a giant clock a dozen stories above 1920s Los Angeles. It is one of the most iconic images in cinema, and the star hanging there was missing his right thumb and forefinger, lost when a prop smoke bomb exploded in his hand in 1919. This episode breaks down Harold Lloyd's Safety Last!, from its cheeky subversion of the era's Safety First industrial campaign to the plot of a small-town clerk faking success for his girlfriend and pitching a publicity stunt that forces him to scale a 12-story department store himself.

We explain why slapstick gags like the pigeons, the mouse, and the tennis net tighten suspense rather than relieve it, and then reveal the optical mechanics of the climb: false building facades built on the edges of real rooftops, the flattening effect of 1920s lenses, and the cre ...