Although I am registered and logged in, I am unable to watch a show. Help!

I'm an Apple user (iMac) using the latest version of Safari. I'm trying to watch an old episode of "In The Wild Frontier: Daniel Boone." I can find the episode on IMDb, but my browser does not show the yellow rectangular box that appears ion screenshots in the Help section (instructions indicate that clicking on it should immediately play the episode). I've now spent about an hour trying to get this right, to no avail. Clearly I'm doing something wrong. Any help would be appreciated. Thanks!