This is Monster: BTK. The first two episodes are available on January 13th. And listen to the first six episodes, completely ad-free, with an iHeart True Crime+ subscription.

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January 1974. Four members of a family are killed in their home in Wichita, Kansas. Investigators are mystified. Nothing like this has ever happened before in Wichita. Little did they know, this was just the beginning.

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The killer's face comes to light. This is not who we were expecting. How did this man become a ruthless murderer? And who else did he kill?

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The killer strikes again. This time, he stalks a young college student. His methods improve, but not without some failure. He reconsiders his choices. But realizes it's too late. It's time to double down.

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A botched murder plan leads the killer to an unsuspecting door. Inside, the killer does something he can never undo. Later, he brags about his deeds in taunting letters to the police and media.

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The killer has become BTK. But he must also maintain his facade as a normal family man. Can he reconcile his inner Dr. Jekyll and Mr. Hyde?

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BTK has killed again. But then, unexpectedly, he stops. Until years later, when he can longer hold it in any longer. He must be known.

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An inside look into the final episodes of 'Monster: BTK.' Which are available early with a subscription to iHeart True Crime +. Or, you can wait for the episodes to release wide, every Monday.

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