An exceptional suspense story is always a matter of how it's told, of the fine art of unravelling—if that word doesn't impute too haphazard a character to a process that is very precisely controlled; and no one in the business today knows and practices its secrets with more finesse than Helen MacInnes.

The scene of ["Decision at Delphi"] is Greece, and the goings-on have to do with an extreme anarchist minority, whose leader, an ex-guerrilla fighter, known only as Odysseus, is plotting an assassination which could lead to political chaos. But a former comrade, Stephanos Kladas, has photographic evidence which will identify him, and is smuggling it into Greece in the luggage of Kenneth Strang, an unsuspecting young American assigned to sketch Greek ruins for a travel magazine. When Stephanos disappears, Kenneth becomes involved, and it is then that Miss MacInnes' technique takes over, teasing and tautening the suspense until almost the final page.

Characterization under such circumstances is relatively unimportant; indeed, anything very interesting in itself would only get in the way. So Kenneth is a nice, intelligent, hard-working hero, an architect who is enough of a poet-maverick to prefer free-lance illustrating to designing office buildings, and boyishly manly in the way ladies love to imagine men to be, and in which they almost invariably are not….

The remaining personae and situations are standard: the masterful police inspector, the shady travel agent, the stuffy British diplomat and his indiscreet wife; a beautiful dark girl who dashes in and out with flurried warnings, and a mysterious white yacht which meets an American ocean liner at Gibraltar and carries away certain even more mysterious passengers; and of course murder, kidnaping, secretly delivered letters, shadowing policemen, and enough puzzled, questioning dialogue to make it all sound like a quiz show much of the time.

To all of this, Miss MacInnes also has added a glamorous gratuity: landscapes from Taormina to Sparta, all freshly observed and deftly sketched into the background….