It was the final days of the year, that quiet stretch between Christmas and New Year’s when the city usually slowed down. Instead, Edmonton was about to face one of the worst crimes in its history.

On the evening of Monday, December 29, 2014, police were called to a home in southwest Edmonton for a weapons complaint. Inside, they found a woman dead. At first, it appeared to be a single homicide.

But hours later, officers were sent to a second house in north Edmonton to check on the occupants. When they entered, they found seven more bodies inside the home, including two young children.

The person believed to be responsible was missing.

As police worked through the night, they were left with urgent questions—where was the suspect, what had happened in the hours leading up to the killings, and why had so many lives been taken?