Big as a fridge and quick as a cat, Gary Hirte exploded off the defensive line, smacking a running back to kingdom come. Under the Friday-night lights, roars of approval swept from the bleachers at Weyauwega-Freemont High School, in a little Wisconsin town. Affectionately known as "The Big Hirte" for his 6-foot-3, 280-pound frame, this affable, curly-haired blond was no dumb jock. Besides being an all-conference football player for the Indians, Hirte was ranked second in the senior class. He was an Eagle Scout and a member of the prom court. In his spare time, he worked at a local ice-cream shop. But police say this hometown golden boy harbored a terrible secret.

The football team's winning season wasn't the only big news in north-central Wisconsin last fall. An unsolved murder in nearby Wolf River Township had stymied police. Glenn Kopitske, 37, an eccentric loner, was found dead in his living room by his mother last August--naked, face down, a gunshot wound in the back of his head, two stab wounds in his back, another in his heart. After five months, the case had grown cold. Then, in January, a call came to police from Olivia Thoma, a college girl in Green Bay. Thoma said she had met Hirte at a county fair, and he had bragged to her about killing Kopitske. Police taped a phone call between Thoma and Hirte in which, they say, Hirte talked casually about murdering Kopitske, saying he had done it "just to see if I could get away with it."

The next day Hirte was summoned to the principal's office, where police slapped cuffs on the boy, then 17, and led him away. Inside Hirte's modest home on Ann Street, police found what they believe were the murder weapons: a 12-guage shotgun and an eight-inch knife. In his bedroom were Kopitske's car keys--police believe the boy was keeping them as a "trophy." Hirte's attorney, Gerald Boyle, a prominent Milwaukee lawyer who once defended Jeffrey Dahmer, denies Hirte is guilty of the killing.

Hirte's arrest shocked Weyauwega, a town of 1,800 with its quaint Main Street straight out of a Frank Capra movie. "This community saw him as the perfect kid," says Staci Larong, a 37-year-old nurse, sipping coffee at the counter of a cafe. Hirte was the first Weyauwega boy in 20 years to make the Boy Scouts' highest rank. Mayor Howard Quimby was Hirte's adviser for some of his merit badges. "He's the kind of kid who's so smart and determined that he can do anything," says Quimby.

The case conjures chilling echoes of the 80-year-old saga of Leopold and Loeb--two brainy University of Chicago students who killed a boy in a quest to commit the perfect murder. They didn't get away with it. Neither will Hirte, say prosecutors, who believe they have a tight case. Besides Thoma, they say Hirte boasted of the killing to some 30 students at his small high school (enrollment: 396). But the kids said nothing until questioned by police. "That's the big question. Why did they keep quiet?" asks Ken Hardwicke, editor of the Chronicle, the local newspaper. "In a small town, people protect their own."

Hirte is being held in Winnebago County Jail on $400,000 bond. At his arraignment in Oshkosh last month, Hirte, now 18, seemed the picture of easy confidence. (Wisconsin has no death penalty. First-degree murder brings automatic life imprisonment.) He smiled. He chuckled. When his lawyer motioned for his ear, Hirte responded lightheartedly: "What's up?" About 30 students were in court. "He's a friend, a good guy," says one. Deputy prosecutor John Jorgensen has a different view of the accused: "He's cocky."

Everybody knew Gary Hirte was going places--but nobody figured it would be a jail cell. Just before his arrest, Hirte was awarded a scholarship to St. Cloud State University in Minnesota. He told friends he wanted to pursue a career that fascinated him: criminal justice.