Nikolas Cruz was determined to burn Valentine’s Day 2018 into memory. After a ride-sharing service deposited him on the campus of the Parkland, Florida, high school from which he had been expelled, authorities said, the 19-year-old entered a stairwell, uncased his semi-automatic rifle and proceeded to unleash hell upon the students and teachers at Marjory Stoneman Douglas High School. Cruz, who apparently left the scene after blending into the crowd of panicked former classmates to get past responding police, was later arrested and charged with conducting the attack that killed 17 teenagers and adults and injured at least 15 more. As the details of Cruz's life have emerged after the shooting, it has become clear that ample warning signs had emerged indicating that he was troubled and posed a threat.