The Zapruder film (specifically the frames in which Kennedy is shot) is shown several times. This is a very low-quality video, but still graphic. We see blood burst from Kennedy's head, and looking closely, we see a piece of bone protruding out.

Autopsy photos in color show a large gash on Kennedy's head that looks like a cut or a stab wound.

The Zapruder film is shown several times, which could be quite disturbing to some. The entire film centers around a murder cover-up/conspiracy theory, and so it's dark in tone.