TV version of an Agatha Christie mystery puts a legion of legends on the line

What becomes a legend most? Something that lives up to the legend.

When you decide to cast Helen Hayes as Miss Jane Marple, the Agatha Christie character almost everyone associates with Margaret Rutherford, for instance, at least a couple of legends are on the line. (I mean, it's not as simple as swapping Roger Moore for Sean Connery in the latest James Bond movie.) Then, if you throw in John Mills and Bette Davis -- in a couple of roles and an ill-conceived venture that can't help making them look bad -- two more shining legends may be in for a little tarnishing.

Finally, Agatha Christie has a formidable reputation for putting together a flawless murder mystery, which is decidedly at stake here.

Well, by the time Murder With Mirrors (CBS, Wednesday, Feb. 20, 9-11 p.m.) has shuddered to a halt, just about the only legend that remains unblemished is that of Margaret Rutherford, the person who didn't appear in the thing.

This made-for-TV movie begins promisingly enough, as Miss Marple is swept suddenly into the life of her old friend, Carrie Louise Serrocold (Bette Davis), who is living at Stoneygates Hall, which her husband has turned into a progressive work farm for juvenile delinquents. The place also turns out to be a veritable snake pit, what with the British bad boys, most of whom are off their rockers, and the upper crust, who keep stabbing each other in the back (and occasionally shooting each other in the head). There are also the usual suspense yarn goings-on: light circuits failing, poisoned glasses of milk, bodies popping up like crocuses.

In good murder-mystery tradition, a dozen or so suspects are thrown at us in the first 15 minutes or so. One character ``was murdered because he must have known who has been trying, slowly and coldbloodedly, to poison my wife.'' And somebody is trying, slowly and hamhandedly, to make fresh mystery out of this stuff. Unfortunately, ``Murder With Mirrors'' doesn't offer the suspense of your average ``Columbo'' episode.

The worst of it is that the great Helen Hayes is caught trying to create a cute character that will somehow live up to the simple hilarity Margaret Rutherford so effortlessly affected. (Miss Hayes also played the same character last season in ``A Caribbean Mystery.'')

Everybody else stumbles around in what begins to look decidedly like a giant game of Clue. The direction is wooden. Only Leo McKern (Inspector Curry) comes off with any real aplomb.

What becomes a legend most?

In this case, it's knowing enough to stay out of a really bad TV clunker.