A BOMB is a bomb is a bomb. And that goes double for "The Manhattan Project," a low-key, high-tech, out-of-touch tale of a teen who builds his own personal nuclear projectile for a science project. It's an ambivalent adventure patterned on the likes of "WarGames," but without the humor or action.

John Lithgow, as a kindly nuclear weapons designer, gets top billing, but young Christopher Collet has the leading role as a 17-year-old whiz kid who sets out to join the world's most exclusive and explosive club.

Lithgow starts seeing the boy's mother after moving to Ithaca, New York, to make secret super plutonium. In a fit of Oedipal pique, subconscious of course, the boy steals the plutonium and uses it for his homemade warhead. He's no peace activist, mind you, but he would like to impress his girl (Cynthia Nixon). She tags along on this radioactive adventure, exposing herself to lord knows how big a dose of deadly isotopes.

The boy, a cold and hostile brat, completes his project in the family garage, without concern for his neighbors, his friends or his mother (Jill Eikenberry), never mind the people of New York and Pennsylvania. The boy's amoral, but Lithgow, who sounds exactly like Bob Hope in this movie, has an awakening when he realizes he makes bombs, too.

Both performers flounder under the uninspiring leadership of director Marshall Brickman. The co-author of such Woody Allen classics as "Manhattan" and "Annie Hall," Brickman cowrites this story with deliberate neutrality. He takes no stand on the hero, nuclear weapons, or production of plutonium. And we're supposed to forget that the plot, with all its high technicalities, is full of holes. After all, the kid is a genius and geniuses are the equivalent of fairies in movies today.

"The Manhattan Project" is an unattractive film, grey and industrial, with a tinny, poorly selected score that sounds like it was written for an Italian sex farce.

At long last, it all comes to an end when the boy and his bomb become the objects of a government manhunt. Rarely am I on the side of the military-industrial complex, but I was cheering these G-men on.

They really ought to ban this bomb.

THE MANHATTAN PROJECT (PG) -- At area theaters.