Plot Synopsis

BLOOD RUNS COLD is a one-hour docuseries that tells stories of individuals who went to unimaginable lengths to uncover the truth after the devastating loss of a loved one, where the crime went unsolved and the perpetrator was unpunished. On Labor Day 2018 (Monday, September 3) at 7pm ET/PT -- as part of Investigation Discovery's inaugural Labor Day programming event, an "All DeLong Day" marathon -- ID aired a sneak peek of BLOOD RUNS COLD. In this special preview episode, "One Billboard Outside Tucson," a young mom goes missing, and her own mother takes it upon herself to uncover the truth behind her disappearance. She'll go to any lengths to get justice for her daughter, but the consequences of her quest prove tragically fatal. BLOOD RUNS COLD had its official series premiere on Sunday, November 4, 2018 at 9pm ET/PT on Investigation Discovery. In this new episode, "Bonded by Grief," the murders of two young boys puts a tragic end to their short lives, but kickstarts a lasting friendship between their mothers. When the case goes cold, the women begin their own quest for answers.