I've never read any books by David Hagberg, though he seems to have been prolific and at least somewhat appreciated writer of spy thrillers, mainly in the 21st century. He started out in the mid-seventies, penning Nick Carters and Flash Gordon paperbacks without a byline and several one-off horror/SF paperbacks, such as the cult favourite Croc. He died in 2019.
I've now read one of his Nick Carters, called The Istanbul Decision. It came out originally in 1983, and Hagberg's titles for his AXE novels are all pretty similar: you have your The Ouster Conspiracy, The Vengeance Game, The Strontium Code... This one is about Nick Carter trying to lure a Soviet spy into a trap by using a double for the spy's daughter who the Americans have kidnapped. It's very complicated, but not very intriguing. The book races on, but I didn't feel much for the characters. The climax takes place in the Orient Express. I don't remember much about the book anymore.
Someone said that Hagberg was one of the writers who made the Nick Carter series too realistic and humorless in the early eighties. There's lots of action, but none of it is zany or far out.
I'm still intrigued by his other Nick Carter, Death Island (1984), that was published in Finland as "Blood-Hungry Man-Eaters" (Verta janoavat ihmissyöjät, that is).
