In her opening statement, Crown attorney Susan MacKay told the jury in William Sandeson's first-degree murder trial what they would witness in Nova Scotia Supreme Court would not be as smooth as what they see on TV or Netflix. She was correct; the bureaucracy of justice would mean lengthy delays, including an attempt at a mistrial, but the case to convict a young medical student for killing a fellow student in a bid to pay off student loans would be every bit as dramatic as a cinematic production.

On Sunday, after a two-month-long trial and 22 hours of deliberations, the jury of six men and six women found the aspiring doctor guilty as charged. Immediately, sobbing and clapping erupted in the courtroom.

"Thank you," exclaimed one of the victim's family members. William Sandeson showed no emotion, no reaction.

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"Turn around and take a bow, Billy," his victim's mother, Linda Boutilier, shouted as he was led out of the courtroom.

Outside, Ms. Boutilier sobbed with relief, "I can actually sleep for a change."

On Aug. 15, 2015, Mr. Sandeson and Taylor Samson were planning a drug deal in which Mr. Sandeson was to buy nine kilograms of marijuana from Mr. Samson for $40,000. Mr. Samson left his wallet and keys at his apartment, told his girlfriend he was going a couple of houses down and that he'd be right back. He hasn't been seen since and his body has never been found. Mr. Sandeson was arrested three days later.

The trial could have been derailed by a surprise twist. The defence asked for a mistrial when it discovered a man it had hired as a private investigator went to the police with what would become some of the most compelling evidence.

In the absence of the jury, the court heard that Bruce Webb was tasked with finding out what two potential witnesses might say under pressure. For 14 months, these witnesses had maintained they didn't see anything. When pushed by Mr. Webb, they confessed they believed they had seen the aftermath of a murder.

The defence argued the testimony may never have become part of the Crown's case if its own private investigator hadn't gone behind its back.

Mr. Webb told the court he felt compelled to help police. When he interviewed witness Justin Blades, the young man was distraught and wanted to come clean. "I also felt that, at that point, if I didn't come forward I would be obstructing justice," Mr. Webb testified.

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Later, in front of the jury, Mr. Blades and Pookiel McCabe, both friends of Mr. Sandeson, would go on to testify that, on the night Mr. Samson was last seen, they saw a man slumped over on a chair in Mr. Sandeson's apartment after hearing a loud bang, "pints and pints of blood" all over the floor, and Mr. Sandeson going around "in panic mode" holding bloodied money.

"When you see a horrific scene like that, that is burned into your head," Mr. Blades told the jury.

During the trial, the court heard and saw what was described as an "overwhelming" amount of evidence, with dozens of Crown witnesses and 100 exhibits.

Many spectators showed up in the courtroom from day to day, enthralled with a case that included a number of young, ambitious students studying not only medicine, but physics, commerce and one who was even working on a PhD in chemistry. All of them were students at Dalhousie University.

In the summer of 2015, Dalhousie had been already been through a tumultuous period. It had been several months since the Dalhousie dentistry scandal, in which male members of the class launched a sexist Facebook page about their female colleagues, made national headlines.

At the time, Mr. Samson was a fifth-year physics student. Friends and family say he sold drugs to pay his way through university. "I didn't like it, but I was aware of it," his mother told the court.

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Mr. Sandeson was also a drug dealer and a track-and-field athlete, just days away from starting medical school.

In the trial, the Crown argued Mr. Sandeson never intended to pay for the drugs, plotting instead to lure Mr. Samson to his apartment before shooting him in the head, taking the drugs and disposing of his remains.

Police testified they found blood spatter all over the apartment, Mr. Samson's DNA on Mr. Sandeson's gun, a fired bullet in the window frame and a backpack full of blood-stained money. They also found many bags of marijuana at Mr. Sandeson's brother's apartment.

The Crown argued the motive was greed and financial gain. Mr. Sandeson's bank manager testified he had withdrawn nearly $73,000 of a $200,000 line of credit meant for medical school. The jury also saw texts between Mr. Sandeson and his parents in which they expressed concern about his debt. On July 17, 2015, Mr. Sandeson got a text from his father saying his mother had received the mail that day. "She's mad about the credit line," he texted. Mr. Sandeson replied, "Well she has no need to be. Will be paid off by September."

Six-and-a-half hours after Mr. Samson was seen entering Mr. Sandeson's apartment on surveillance video, Mr. Sandeson texted a friend: "Student loan paid off. I'm completely squeaky clean now."

His lawyers argued police botched the investigation, impacting the quality of the evidence by not wearing protective clothing, sitting at the kitchen table in Mr. Sandeson's apartment and using the washroom. Defence lawyer Eugene Tan said there were leads that weren't pursued, accusing police of being selective and trying to "shoehorn the evidence to fit the result" at the exclusion of other possibilities. He told the jury that the officers' failure to follow up on other names brought forward by Mr. Samson's family and friends was "troubling."

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While Mr. Sandeson didn't testify, the jury did hear from him directly as he sobbed in an interrogation video that lasted nearly eight hours.

In the video, Corporal Jody Allison tells Mr. Sandeson that people who want to become doctors generally want to help people. "I think that you're a good person. I think you've got a good heart."

He continues, his face only inches from Mr. Sandeson's. "Don't make me think that you're a monster, bud. Tell me the truth."

After a long silence, he tries again. "You know where Taylor is."

"I don't know where he is!" Mr. Sandeson exclaims, continuing to cry.

In the same video, Mr. Sandeson eventually tells police various versions of how things unfolded on the evening of Aug. 15, 2015.

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First, he tells police about the drug deal, but says he was only planning to buy a few grams and that Mr. Samson never showed up. Next, he tells police three unknown masked men entered his apartment through the front door, struck him and Mr. Samson and, when he got up, the men were gone and so were Mr. Samson, the drugs and the money. Finally, he changes his story again, saying two intruders wearing full-body Morphsuits were waiting in his roommate's bedroom, that they shot Mr. Samson in the back of the head, put his body in the duffle bag along with the drugs and the money, and left him to clean up.

There remain many questions as to the whereabouts of Mr. Samson's body.

In the days following Mr. Sandeson's arrest, police would undertake an extensive search of an expansive area of Mr. Sandeson's family farm in Lower Truro, N.S., about 100 kilometres north of Halifax. The jury would later hear Mr. Sandeson's phone pinged in the area the morning before he was arrested.

"We were looking for a body," Sergeant André Habib said. He said his job was to sift through cow manure and drain a lake after cadaver dogs indicated there may be human remains there. Searchers never found a body, but they did find an old abandoned ice-cream truck and inside it, many items of interest – including a backpack the officer testified had a "strong decomposing rotting smell" coming from it.

Court heard Mr. Samson's DNA was found on several items discovered in the ice-cream truck, including a large, black duffle bag. The jury also saw surveillance video of the 6-foot-5, 210 pound Mr. Samson entering Mr. Sandeson's apartment – on the night of his disappearance – carrying a large, black duffle bag. An expert testified Mr. Samson's DNA was located in the trunk of Mr. Sandeson's car.

In her closing argument, Crown attorney Kim McOnie told the jury, "This is not a Hollywood film where masked invaders or Morphsuited intruders bust in through a window, shoot someone and take the money with them. This is reality, a reality where every shred of physical evidence … points to one person as being responsible for the death of Mr. Samson."

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Mr. Sandeson is to be formally sentenced on July 11. A conviction of first-degree murder in Canada comes with an automatic life sentence and no chance of parole for 25 years.

"I want my son back," Ms. Boutilier said. "I'm going looking after this trial and I'm going to find my son. If he doesn't want to help us, then fine, I'll find him on my own. I'm not going to stop."

Mr. Sandeson's lawyer declined to comment on whether his client will appeal the verdict, saying the defence wishes to respect Taylor Samson's family.