James Dark is a pen name used by an Australian writer named James McDonnell. He wrote a lot, and I mean a lot, of books, including those in the Mark Hood spy series. Some of the latter were published in the U.S. by Signet at the height of the spy craze. I have four or five of them, and I must have read a couple back in the '60s, though I don't remember which ones. I pulled one off the stack the other day just to have a look, and I recognized the opening scene, in which the sea begins to boil near some Japanese fishing boats just before they're destroyed. In rapid succession, we have more boiling seas, a sex scene, a scientist kidnapped by a some fake medics, and another scientist grabbed by a guy wearing a jet pack right out of the Rocketman serials. That takes up about the first twenty pages. And there are only 1oo left to read. The print's big, too.
As you've probably guessed, this book makes anything in Fleming's James Bond series (and I'm counting the movies) look like a model of realism. Before it's over we've taken into the cave of Genghis Khan where one of his descendants has set up shop and from which he intends to (you guessed it) rule the world. (The cave, by the way, was revealed by a nuclear test, and the Khan descendant and his minions entered it "after the radiation had receded." In case you were wondering.)
He doesn't have a chance, however, against Mark Hood, who's remarkably stupid at one minute and brilliant at the next. The book seems to head in one direction and promise one thing, but then it veers off into another direction entirely, dropping the plot idea that had seemed to be developing for another one. You want character development and logic? You've come to the wrong place.
This kind of thing can be fun, though, if you just turn off your mind and go with the flow, but it's definitely a relic of an earlier time. I suspect there's only one other person besides me who can still enjoy it: this guy. If you want to try, though, you might get a kick out of it. (And don't ask what that is on the cover. I have no idea.)