Reprinted from yesterday's late edition.

Those who are always right about Agatha Christie puzzlers until the last three minutes will find they are betting a thousand again at Olney's "Towards Zero," which Tuesday night opened a three-week run at the countryside's summer theater.

Christie has become an Olney tradition and this one was adapted by her and Gerald Verner from one of her more than 80 novels. Though a modest London run did not lead to a New York production, it's slowly been getting the recognition trick endings inspire.

Camilla, Lady Tressilian, has been unwise enough to invite both the first and second wives of a favored young man for a fortnight in her Cornish coast home and will suffer for such gracelessness. The question becomes, "Who Killed Camilla?"

Obeying the dictates of the critical craft, I can say no more about subsequent events. One may remark that a golf club, a pair of gloves, a bloodspattered dinner jacket and some yards of hemp are involved, as are a Scotland Yard superintendent, his impetous nephew, Lady Tressilian's lawyer and a dangling suitor. For four of the six scenes, the plot plods along with little of the customary Agatha case. But the final two are not disappointing and may give resourceful folks ideas about how to punish loved ones.

Agatha Christie audiences create, during scene shifts, a hum unlike non-Christie audiences. There is that quality here, the rising bubbles of faintly nervous laughter, the superior chuckles from those who know who done it and the soft rib punches which indicate the one-uppers are thinking.

Leo Brady's staging bears down heavily on advance punches, irritating while the plot is building, rewarding when the ax falls. The purest of the performances are from Roger Barron and Judith McGilligan, the formerly married couple, whose innocence is indisputable. J. Robert Dietz, one of Olney's longtime favorites, is back to unravel the plot strings and Mimi Salamanca, despite a fairly absurd make-up job, is firmly in control as the very subtle old lady one finds in Christie yarns. The combined accents of all the 11 characters are a melange, perhaps, of Block Island, Nantucket and Outer Beverly Hills, a matter which will confuse only purists.

Rolf Beyer's setting so fills the Christie scheme that a burst of applause greeted it at curtain's rise: Clearly this is a drawing room where murder will have polite if passionate inspiration. Olney's Agatha Christie choice this summer will satisfy her fans so long as they stay for the final snapper.