The first episode is called "The Mystery of the Haunted House," and that title is a complete rip-off, because there's no haunted house in the show, just a nightclub/restaurant/wood-panelled hellhole named The Haunted House. This is kind of a thing in this series: the titles all sound like something supernatural might be going on, and instead it turns out to be smugglers or spies. It's like Scooby Doo with more hair.
About the hair. I know it was the seventies, but these boys have a lot of hair. Sort of...feathery, fluffy hair. I think the hair might be why they were considered attractive. It's the only reason I can come up with, because the guy playing Frank Hardy has a pointy chin and smirks a lot, looking uncannily like John Travolta (only, hold on, I just realized this was the same era in which Travolta was also considered good looking, so I guess pointy-chinned smirkers were in style then?); the younger brother, Joe, is played by Shaun Cassidy and looks like a nervous hamster. You think I'm kidding, but I'm not.
|That's Hamster on the left and Travolta-ish on the right.|