Yes, many of you will remember these wonderful books. If you held onto them, good for you. They’re costly today. It’s one of many series we plan to review at We Are the Mutants (launch still scheduled for late August or early September).
The Three Investigators debuted in 1964 and went through several editions. Pictured here are a few of the “Hitchcock” and “Keyhole” editions (the ones I read), published between 1979 and 1987, with cover art by Robert Adragna. Read more about Adragna, and see more of his fantastic covers, here.
2 Warps to Neptune 
love the colors and style of the artwork!
I only had a couple of these as a kid, but loved them all. The idea of having your headquarters in a junkyard where no one could find it! And I loved the eerie green Haunted Mirror cover.
You were braver than I was. I had quite a few of these books but that cover gave me the creeps more than any other. Now I know the name of the artist responsible for some of my early nightmares!
I remember being drawn to these as a kid, like others because of the covers, but for some reason couldn’t make it through the stories. I never see these at sales, but I’d definitely pick them up if I did and give them another try.