ONE OF THE AREA'S best road shows has just started a new run - and tickets will be handed out freely all over Maryland. At Gov. Harry Hughes' request, the Maryland State Police have launched another all-out anti-speeding campaign. They have brought back the intensive patrols the fancy radar devices, the airborne speeder-spotters and the cast of unmarked vehicles - including sports cars, pickup trucks, a motor home and a tractor-trailer named 'Mother Goose' - that made so many hits in 1975.

Speeders who escaped earlier rounups should not assume they can do so again. The state police have added some new tactivs to counteract drivers'radar detectors and citizen-band radios. They plan to give special attention to speeding commuters, and to hurtling buses and trucks. And if all else fails and traffic on some major arteries keeps exceeding 55 miles per hour, the police may resort to 'rollingroadblocks,' with marked patrol cars driving precisely at the speed limit in all lanes.

It's a show we applaud.Enforcing the 55-mph speed limit is an excellent way to save lives. It is, as well, a good way to save fuel. After the national limit was imposed in 1974, highway deaths dropped dramatically and gas consumption increased more slowly than before. But in Maryland, as elsewhere, traffic speeds, fatalities and gas consumption have started accelerating again. Deaths on Maryland roads, which had dropped from 822 in 1973 to 674 in 1977, rose to 728 last year.

Of course there's a large element of theater in the Maryland approach to curbing speeders. But that's fine. Besides catching some lawbreakers, the innovations attract publicity and alert more drivers that nay vehicle or tree they speed past might contain a cop. In 1975, the state police had to hand out 35,000 tickets in siz weeks to make the point. This time around, more drivers may slow down before they are stopped.