Neal Adams writes and pencils Teen Titans 20 (March/April 1969), with Cardy on the inks.
The story introduces a masked hero, Joshua, a master of electronics. He breaks into the Titans Lair, confronting Robin, Speedy, Kid Flash and Wonder Girl, and convinces them in joining him in stopping some young anti-police protestors, who are being used by criminals. The younger brother of Joshua is one of the protestors, and the boy will not listen to him, not trusting the older generation, which is why he calls in the Titans.
The story looks great, and introduces the Fat Man, a crime lord who, it is revealed, was behind the Scorcher, and other, unspecified, foes that the Titans have fought. With the teens now messing up his latest plan as well, the Fat Man decides it is time to take direct action against them. And yet, somehow, this story doesn't quite come together for me.
The Fat Man is working on Operation: Jericho, which involves releasing a monstrous creature. The thing sure looks scary, but it gets defeated before it even gets free. I think part of my problem with the tale is that the Teen Titans themselves have nothing really to do with defeating the major scary thing in the issue. Joshus does it, but completely unintentionally. Screwing up Operation: Jericho is an unexpected side effect of the electronics he is using.
The aliens from Dimension X, the ones that had been trying to invade the Earth through the school, also return in this story, and the Fat Man is working in conjunction with them. So their plans get messed up as well, though no one but the Fat Man and the readers even know they are involved.
The story continues in the next issue.