When we were kids my mom wouldn't let us watch Lost in Space because we'd have nightmares. They had a marathon of the show on one of the cable channels recently and we all laughed about it. My kids couldn't believe that we were terrified over the "monsters."
Alfred Hitchcock would have to be the number one, just because he was used to doing movies in color, but he found ways to graphically illustrate things on TV in black and white. Hershey's syrup for blood. Use of shadows. Framing of shots