NEWMARKET, Ont. -- A woman's "obsessive, relentless" love for a man her parents disapproved of led her to plot their murder in a staged home invasion, but her plan unravelled when her father survived the attack, prosecutors alleged Wednesday.

Jennifer Pan hatched the plan after her parents made her choose between them and her co-accused Daniel Wong, who had been her high school sweetheart, Crown lawyer Jennifer Halajian told a Toronto-area court in her opening statement.

Though she appeared to bow to their demands, Pan resented them and continued to see Wong, with whom she hoped the spend the rest of her life, Halajian said.

"As long as her parents were alive, that hope was dead," she said.

Pan, Wong and three other men -- Eric Carty, Lenford Crawford and David Mylvaganam -- are charged with first-degree murder in the death of her mother, 53-year-old Bieh Ha Pan, and attempted murder in the shooting of her father, Huei Hann Pan.

While they didn't all pull the trigger, each "participated in carrying out Jennifer Pan's plan to murder her parents," Halajian said.

Others were involved in the plot and some of the intruders aren't among the accused in this trial, she said.

The judge overseeing the trial told the jury that just because all five accused are tried together doesn't mean they should get the same verdict.

Pan, 27, initially appeared to be a victim in the Nov. 8, 2010 incident at her family's home in Markham, north of Toronto.

But the Crown said her story -- that three people had broken into the house, tied her up and shot her parents -- quickly started falling apart once it became clear her father would survive.

In a 911 call played in court, Pan sounded distraught as she pleaded for help. At one point, a man's screams can be heard in the background.

"I heard shots like 'pop,"' she said. "I think my dad's outside and he's screaming."

Prosecutors allege she came up with the murder plan earlier that year after a receiving an ultimatum from her parents. The couple, refugees from Vietnam who had high expectations for their children, had just discovered much of what they believed about their daughter was "a lie," Halajian said.

Pan had never attended university, much less graduated, and she was living with Wong in Ajax instead of with a roommate as she told them, the lawyer said.

"They told her she had to make a choice," that she could come home for good or be estranged from the family, she said.

Pan's return to the family home strained her relationship with Wong, but she nonetheless asked him to help orchestrate the plan, the Crown said.

Court heard Wong, now 28, had found a new girlfriend and Pan was desperate to lure him back, making up stories that she had been raped and threatened and needed his protection. It seemed to work, for a time, prosecutors said.

The Crown said Wong put her in touch with Crawford, who acted as go-between for the group. Carty and Mylvaganam's role, meanwhile, was to go to the house "and kill two innocent parents," but it's unclear if Carty ever made it inside, Halajian said.

Over months, they made arrangements through text messages and calls on various cellphones, even driving by the house to scope it out, she said.

Pan was to pay $5,000 for each parent killed, the lawyer said. It's alleged the money would have come from her inheritance and the payout from her parents' life insurance, of which she and her younger brother Felix were the sole beneficiaries.

"She was coming into a lot of money once her parents were dead," Halajian said. "That's how she was going to take care of Daniel Wong."

As the date grew closer, Pan began to doubt Wong's affection. On Nov. 2, less than a week before the killing, Wong texted her saying he loved his new girlfriend, according to messages shown in court. "I feel the same way you feel but about her," he wrote.

When Pan said she would call off the plan as a result, Wong texted: "U said you wanted this with or without me."

The night of the home invasion, Pan's parents were asleep when she went downstairs to unlock the front door, having just spoken with Mylvaganam, the lawyer said.

Her father was woken by a man pointing a gun at him, then he was taken downstairs with his wife, she said. He saw his daughter talking softly with another man, she said.

Pan's mother repeatedly begged the intruders not to harm her daughter, Halajian said. At one point, they assured her no harm would come to the young woman, the lawyer said.

Her father lost consciousness after he was shot in the head. Halajian said he was shot in the face and shoulder.

When he came to, his wife was dead, she said. Bieh Ha Pan had been shot in the back, the base of the head and again in the head, this time at point blank.

The father managed to flee to the neighbour's house before paramedics arrived, but he remained in a coma for several days.

Felix Pan broke down on the stand Wednesday as he recalled calling his sister hours after the incident, to "find out what happened." In the prisoners' box, his sister, who wore black from head to toe, cried so intensely that court recessed for several minutes.

Halajian said Pan was visiting her father in the hospital along with several relatives when she learned his injuries weren't fatal.

She immediately called Wong on a hospital pay phone, even though family members had offered to lend her their cellphones, the Crown said.

Pan was arrested on Nov. 22.