Due to the graphic nature of this killer's crimes, listener discretion is advised.

This episode includes discussions of murder, sexual assault, rape, attempted suicide, child and animal abuse.

We advise extreme caution for children under 13.

About a cold January evening in 1972, 36-year-old Joseph Calliger sat in the back of a cab.

He thumbed the pistol in his coat pocket as he looked out the window, searching the streets of Philadelphia.

He was looking for his kids, Isabelle and Tommy, who had run away from home a few days earlier.

Finally, he spotted them leaving a movie theater and told the driver to follow them.

When they caught up to the teens, Joe got out of the cab.

He pulled the gun out of his pocket and pointed it at his kids, ordering them into the car.

Huddled together in terror, Isabelle and Tommy climbed into the back seat.

Joe slid in next to them and the family drove home in silence.

But things weren't quiet in Joe's head.

There was a voice speaking to him, the whole way home.

He listened as God gave him instructions on exactly how to punish his children.

Joe intended to teach the kids a lesson about what would happen to them if they abandoned him.

When he was done, he felt sure they would never, ever leave him again.

Hi, I'm Greg Poulson. This is Serial Killers, a Spotify original from podcast.

Every episode we dive into the minds and madness of Serial Killers.

Today, we're exploring the life of Joseph Callinger, a shoemaker with a dark, disturbing secret.

I'm here with my co-host, Vanessa Richardson.

Hi, everyone. You can find episodes of Serial Killers and all other Spotify originals from podcast for free on Spotify.

Today, we'll look into Joseph's childhood and his descent into madness.

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