Cosmo DiNardo's Descent Into Madness

Cosmo DiNardo and his mother on prom night

By Ralph Cipriano
for Philadelphia magazine

In the middle of a murder rampage, Cosmo DiNardo had an appointment to see his psychiatrist. So on the afternoon of July 6, 2017, the 20-year-old from Bucks County dutifully climbed in the front passenger seat of his mother's SUV, and they headed south on I-95, toward We…