Kitchen-sink suspense: a hectic little British item that starts out as old-fashioned murder mystery, then lurches into a spy-fi tangle, and winds up in a race to prevent a cartoony takeover of all Britain by the Communists. William Denton, visiting professor from Texas, is found shot to death at Carrington College, Cambridge. And the prime suspect seems to be Mrs. Denton--especially since Denton's latest mistress soon turns up dead too. But despite the plethora of love-life motives in the air, Scotland Yard's David Cooper (whose wife and son were murdered by KGB hitman ""Zio"" a couple of years back) suspects that Something Big is going on. What about the ESP-warfare research going on at Carrington? What about the College Master's Communist past? Is someone at Cambridge the top KGB agent in Britain? And could it be Cooper's nemesis Zio who did the murders . . . and who is planning to blow up Parliament, sending the UK into vulnerable chaos? All these puzzles connect up, of course. So the finale has Cooper & Co. rushing, countdown-style, to kill Zio and prevent Britain's collapse, But though the opening chapters have some straightforward appeal, the ensuing hodgepodge (there's also a heavy hypnosis subplot) is sketchy and implausible--and neither mystery fans nor espionage buffs (who've read dozens of better Communists-at-Cambridge thrillers) will be steadily entertained.