[The Hidden Target], one of MacInnes' least persuasive efforts, hardly cried out for a sequel. But here [Cloak of Darkness] is anyway: a drab terrorist-hunt that doesn't even feature the vast scenery or the damsel-in-distress setup that made The Hidden Target fairly readable. Robert Renwick of "International Intelligence Against Terrorism" (Interintell), who saved lovely young Nina—now Mrs. Renwick—from super-terrorist Erik in The Hidden Target, is on Erik's trail again: Interintell has received information that Erik's on the loose in Africa. Furthermore, Interintell has learned that two corporations are involved in illegal arms deals—and that these villains have drawn up a "Minus List" (nine enemies to be assassinated) and a "Plus List" (the bigwigs who are secretly funding international terrorism). Interintell, then, has three new missions to accomplish: track down Erik; warn the people on the Minus List (Renwick himself is one of them); and somehow get hold of the Plus List before it falls into the hands of the USSR or other terrorist-deal-makers. Meanwhile, too, it becomes clear that there's an informer somewhere in the Interintell organization. Unfortunately, however, despite all these Missions Improbable, the plotting here is limp and suspenseless—as Renwick and his cronies wander around (Ethiopia, New York, Paris, Switzerland), find a few bodies, exchange a few shots, knock off Erik, and eventually locate the chateau of super-villain Klaus Sudak. And, though everybody constantly worries that Nina might get kidnapped, she remains a bland, inactive minimatron throughout. So, with no imperiled heroine to identify with and no conviction in MacInnes' sluggish, comic-book terrorism, this is her weakest work ever—but don't underestimate the obliging nature of a long-time, loyal readership. (pp. 755-56)