VICTOR, N.Y. (AP) _ For a decade, theirs was a master-servant relationship of two loners with troubled pasts. But whatever loyalty existed between Michael Stevens and Earl Figley dissolved in a haze of blood, vengeance and betrayal.

Stevens, 54, an intense, manipulative man, goes on trial Monday in U.S. District Court in Rochester, charged with unleashing mail bombs that killed five people, including his girlfriend's mother, stepfather and sister.

And Figley _ a harmless-looking alcoholic who did whatever Stevens asked, from cooking his meals to allegedly picking up a $225 case of dynamite using a phony Vermont driver's license _ will be the star prosecution witness.

This is the story he is expected to tell:

Stevens' father, a grocer, often beat him severely. The effects were easy to see: He fidgeted, had difficulty concentrating and suffered a nervous breakdown in his teens.

After spells as a music promoter and cabdriver, he ran a series of small-time scams. His computer dating service attracted dozens of complaints in five states, and a coupon advertising scheme drew him 20 months in prison.

His tendency to mouth off during his 1987 fraud trial didn't serve him well behind bars. An inmate smashed his jaw.

Just out of prison, Stevens met Brenda Lazore Chevere at a wedding. He was trouble, for sure, her relatives say, and they knew it immediately; they say he threatened them several times. But she, too, evidently had a temper _ once, she slashed Stevens in the forehead with a pair of shears.

Prosecutors say Stevens' anger at Chevere's American Indian family was obsessive; he felt they excluded or slighted him. And at the end of 1993, Figley said in his 43-page statement, Chevere was threatening to leave Stevens and take their 2-year-old son, Noah.

After a pleasant Christmas Day dinner with Chevere's mother, Eleanor Fowler, and 15-year-old brother, Jonathan, Stevens decided ``he would have to stop them (Chevere's family) from supplying her with money or a place to live,'' Figley said.

Figley, 57, said he thought Stevens had disposed of the dynamite he bought for him in Kentucky that summer. But he said that when they delivered the packages on Dec. 27 and Dec. 28, 1993 _ by taxi, private courier and U.S. mail _he realized they were bombs.

One of them blew up in the face of Mrs. Fowler at her home in West Valley, 30 miles south of Buffalo. Another killed her husband, Robert, and a co-worker. Her daughter, Pamela, and a boyfriend were slaughtered while baking pies in their kitchen in Rochester.

Her brother, William, suspicious of the bundle mailed 350 miles to the St. Regis Indian Reservation near Canada, opened it outside his house with a rake. The blast threw him 15 feet, gouging his legs. Shrapnel killed his dog and injured his son, who was standing in the doorway.

Two bombs intended for another daughter and her husband failed to detonate or were intercepted by police.

Hours after the bombings, around midnight, police drove down the winding, dirt road to Chevere's backwoods home. They wanted to make certain she was all right, to ask if she knew why her family had been targeted and check on Stevens.

Stevens, a short, pudgy man with glasses, answered the door in his pajamas. He appeared nervous and upset and, at first, didn't want to accompany Chevere to nearby Rochester to possibly identify a body. Advised that the grieving woman could do with some moral support, he relented.

Just then, Figley poked his head out of the basement. Stevens told the detectives he'd forgotten his friend was visiting. Figley stayed behind to mind Noah, but later agreed to come in for questioning.

Initially, police treated Stevens and Figley as potential victims or witnesses. But suspicions intensified as information from Chevere's surviving relatives and the Bureau of Alcohol, Tobacco and Firearms filtered in.

Investigators noted Figley's disfigured face. He lost his right eye and a chunk of his brain in a 1958 car crash in Michigan. And when they asked the former science teacher for identification, he pulled out a red wallet.

Through the night, they were interviewed casually in separate rooms.

By daybreak, confronted with evidence that a look-alike with a droopy eye and a red wallet was seen in Mount Vernon, Ky., buying dynamite that matched an unexploded bomb, police say Figley admitted helping Stevens deliver half a dozen bombs by taxi, private courier and U.S. mail to Chevere's family.

``We confronted Earl with things that we knew and, eventually, I think he realized we had enough on him so he might as well cooperate,'' said William Barnes, a homicide detective renowned for ferreting out confessions.

In return for a 20-year sentence at a minimum-security prison, Figley pleaded guilty last month to conspiracy to mail dynamite sticks and shrapnel packed in fish-tackle boxes with intent to kill.

But Stevens' lawyer, Peter Pullano, contends Figley orchestrated the attack and said prosecutors have ``shown that they'll deal with anybody to try and get evidence,'' including four inmates who allege Stevens tried to enlist them last year to kill Figley.

If convicted, Stevens could get multiple life sentences. The 33-year-old Chevere still visits him in jail and lives at their redwood-sided house in a clearing at the end of a private road bordered by woods.

``I have no comment,'' she said from behind her doorway.