Exotic locales have always been a big part of the Helen MacInnes formula, and this new suspense-romance (though short on actual scenic description) has more of them than ever--perhaps even enough of them to compensate for one of MacInnes' least credible or shapely plots. Iron Curtain spymaster Theo is in uneasy cahoots with a terrorist-anarchist brigade called ""People's Revolutionary Force for Direct Action,"" and he's masterminding their new project: a 'round-the-world trip in a camper-trailer to size up local terrorist outfits, plus--at trip's end--some unspecified anti-U.S. action involving White House adviser Francis O'Connell. So handsome terrorist Erik's job is to lure O'Connell's daughter Nina, a student in London, to come along (with roommate Madge) on this world tour (disguised as a test run for a new model of camper)--all of which he manages easily. But right at the start, in Amsterdam, Nina just happens to bump into family friend Bob Renwick, who just happens to be a new recruit to ""Interintell,"" a worldwide anti-terrorist agency. The subsequent action, then, will bounce back and forth between the oddly routed camper tour (Nina falls for Erik but impetuously goes off on her own in Greece) and Renwick's Interintell activities: avoiding assassination attempts by Theo's hitmen; unmasking a terrorist headquarters in California; and, after figuring out that Nina's tour is a terrorist front, monitoring the camper's journey. Renwick himself shows up in decorative Istanbul to try to convince Nina to leave the tour (without telling her why); later, on the way to India, Renwick's agents tell Nina the truth, but (for thoroughly implausible reasons) she can't bring herself to leave the tour. And finally, in Bombay, Nina is rescued while the terrorists (including mastermind Theo) are trapped and captured. One mystery remains to be solved, however: what was Theo's plot involving Nina's dad in Washington. . . and is it still an ongoing plan? This is duly sorted out (something about a briefcase-bomb meant to blow up the National Security Council)--but, like the rest of the plotting here, it's unpersuasive and lumpily paced. Moreover, the dialogue throughout is terribly stilted, the Renwick/Nina romance is a dud, and MacInnes has no feel for contemporary characters under age 40. Still--a few of the old-fashioned thriller scenes work nicely enough; and, for readers hungry for maximum atmosphere with minimum sex and violence, always-painless MacInnes is still the very best bet around.