First appearance: Kamandi, the Last Boy on Earth #1 (1972)

Don’t get us wrong, the original Jack Kirby run on Kamandi is the type of colorful, insane Silver Age comic that stirs up all kinds of warm, nostalgic feelings. But here’s the problem: The book's premise is way too close to that of Planet of the Apes to ever be put on film.

In the book, a young human named Kamandi is one of the last surviving humans in a post-apocalyptic world that highly intelligent animals now rule. With the recent Planet of the Apes cinematic relaunch being such a triumph, a Kamandi movie would just come across as a cheap knockoff, despite the quality of the original stories. DC has a hard enough time getting people interested in its movie properties—the last thing the company needs is to look like it’s already out of ideas.