A sea-submarine-and-missile-going action story which is redeemed from familiarity by its efficient air of enterprise and particularly by the presence of one Haggai Godin, one of the many mixed international agents who figure here. On the one hand you have a merchant ship proceeding to Israel with a cargo of missiles; on the other Roger Platt, head of Special Operations -- the ""Cabinet's rusty dagger"" -- and Mason of the C.I.A. and the indestructible Haggai who gets inside Russia and out with the knowledge of a Russian computerized submarine. . . . No waffle, just an authoritative demonstration of the genre which toes a tight line.