Man Held in Plot to Kill His Wife : Violence: Police say the husband’s girlfriend schemed with him to make incident look like a random shooting. They allegedly hoped to collect a $500,000 insurance payoff.

Rebecca Martin, eight months pregnant, was sitting alone in her car in the parking lot of a shopping mall last week, waiting for her husband and 11-year-old son to buy tickets to a movie.

Without warning, someone behind a fence opened fire with an assault rifle, spraying the car with 20 rounds and hitting Martin four times in the back. Rushed to the hospital, she gave birth by Cesarean section to a healthy boy. She was in fair condition Monday afternoon, hospital officials said.

Her husband, John Martin, said he believed she was the victim of a random shooting--an unusually brazen and violent crime in this blue-collar community an hour east of San Francisco.

Soon, however, police came to a different conclusion: They say Martin and his 20-year-old girlfriend, Joann Trethewey, conceived an elaborate plot to kill his wife and collect on a new $500,000 life insurance policy.

By Monday, John Martin and Trethewey were in jail on charges of attempted murder. Police said that Trethewey, overcome by remorse after visiting Rebecca Martin in the hospital, confessed to pulling the trigger.

“This is a very bizarre event,” Pittsburg Police Sgt. Nick Baker said. “We’re glad to be able to put citizens’ minds at rest that there isn’t some sort of random shooter preying on people going to the movies.”

Police said John Martin and Trethewey had planned and rehearsed the murder and callously used Rebecca Martin’s 11-year-old son from a previous marriage in staging the shooting.

Over two months, John Martin had begun a ritual of taking the family to the mall and parking the car in an isolated spot near a fence, saying it was so he could race the boy to the theater.

Last Wednesday evening, when Trethewey began firing from behind the fence, police said, Martin and the boy were 100 yards away, standing in line to buy tickets to see “D2: The Mighty Ducks.”

John Martin, 26, and Rebecca Martin, 32, were married in Las Vegas 2 1/2 years ago after a three-week romance. They moved to Concord, near Pittsburg, where she worked as a bank data processor and he dabbled in various enterprises, such as managing an apartment building.

After John Martin struck his stepson last year, authorities removed the boy from the home for eight months, allowing him to return about two months ago, police said.

In December, John Martin met Trethewey in San Francisco at a mock-combat gallery where patrons shoot each other with laser guns in simulated warfare.

By January, Trethewey had moved out of her parents’ home in San Jose and gotten an apartment near the Martins’ home in Concord. She and John Martin started a business out of her apartment, marketing specialized credit cards. She also befriended Rebecca Martin, who was unaware that Trethewey and her husband were having an affair, police said.

In February, John Martin purchased a $500,000 joint life insurance policy, telling his wife it was to protect her in case something happened to him, authorities said.

According to Trethewey’s confession, it was Martin’s idea to kill his wife, police said. Afterward, they were to collect the insurance money, travel to Rio de Janiero, get married and settle in Los Angeles or New York, where they would study acting.

The murder was planned in such detail that they studied the movement of security guards at the mall, timed how long it would take Trethewey to leave the area and threw rocks into the water at the Pittsburg Marina to practice disposing of the murder weapon.

For the shooting, Trethewey dressed in men’s clothing and wore large boots and ankle weights so that her footprints would appear to be those of a man, police said.

On Wednesday evening, the Martins parked their Nissan Pathfinder in their customary spot by the fence and John Martin and his stepson ran to the theater.

When Trethewey began shooting, Martin threw the boy to the ground in front of the theater as if to protect him from stray bullets, he told police. Then he ran to the car and saw his wife on the ground, bleeding.

John Martin suggested to police that it was a gang-related shooting and said he regretted coming to Pittsburg to go to the movies. He also told police he did not have an insurance policy on his wife.

But police became suspicious, in part because of his statements and in part because the Martins’ car appeared to be the target of a planned assault. They soon learned of the insurance policy and discovered that John Martin owned a 9-millimeter assault rifle that matched shell casings found at the scene.

While police conducted their investigation, John Martin and Trethewey visited Rebecca Martin in the hospital. At the nearby marina, the tide went out and a fisherman found the assault rifle, which police said matched the distinctive weapon owned by Martin.

On Saturday, while police interviewed him at the station a second time, they searched Trethewey’s and the Martins’ apartments. At Trethewey’s home, they found a small library of books on how to commit a murder. Accompanied by two relatives, Trethewey turned herself in Sunday and confessed to the plot, authorities said.

“Their motive was to keep their relationship going--to be together--and to collect on this big insurance policy,” Baker said. “They certainly could have pulled it off. It wasn’t a harebrained scheme. It was very well thought out and very well planned.”