Several optical illusions shown in stop motion footage and animation.
Titles read: "Can you believe your eyes? [superimposed over C/U of a woman's eyes - she winks at us.] Perhaps our tame lecturer will convince you that you can't."
Film probably originates from United States of America.
In animated / stop-motion footage we see several optical illusions being drawn, including the usual ones where lines seem longer than they really are or appear to bend in the middle when they really don't. The fast and jokey commentary adds to the fun.