FOR AN ABC television crew here to film a reality show, Prince George's County offered just a little too much reality. An armed robber held up the front-desk clerk at the crew's Largo hotel last weekend, then pistol-whipped a crew member's wife who happened along at the wrong time. The crew, which is filming an episode of "Extreme Makeover: Home Edition," checked into a better hotel; the county beefed up its police protection; and the show's executive producer delicately referred to the county as "a tricky area."

Prince George's is a tale of two counties these days: In one, signs of vitality, such as the National Harbor project, hold the promise of dynamic renewal; in the other, a spate of violent crime threatens to destroy the county's image and subvert its economic progress. At the moment, the second version seems to have the upper hand.

In Langley Park two people were killed and three others badly wounded in a five-block area in the space of just five days this month. Four of the victims had their throats slashed and the fifth nearly lost a hand when he was attacked by an assailant swinging a machete. In Suitland, a new elementary school is about to open on the edge of a notorious drug market where six people have been killed this year. As The Post's Allison Klein reported recently, school officials are so nervous about grade-schoolers walking through the desolate three-block area bounded by Homer, Hudson and Hurson streets that they have been considering a plan to bus all 600 of the students, no matter how close they live to the school.

Overall, nearly every category of violent crime is up sharply this year from already high rates in 2004. Murders have increased by 25 percent compared with the same point last year, and there have been almost as many robberies and carjackings already this year as in all of 2004.

Confronted with this dangerous crime wave, Jack B. Johnson, the Prince George's county executive, is belatedly hiring more police recruits. A recent police recruitment ad, broadcast on radio and on television, elicited an encouraging flurry of interest. But Mr. Johnson has also undercut his own cause. He joined the county's police chief, Melvin C. High, in criticizing officers as lazy -- a singularly unproductive move. And earlier this month he let spin trump truth by insisting that Prince George's has turned the corner in lowering the rate of homicides. In fact, there have been more murders in the county this year compared to last in every month except May and June, and August is also running ahead of the 2005 totals so far. Altogether, there have been 106 murders in the county so far this year, vs. 85 at a comparable point in 2004. Denial and statistical sleight of hand won't cut the Prince George's crime wave down to size, and Mr. Johnson would do well to level with his constituents.