One week before Queena Phu's Senior prom, the 18-year-old pulled into her local library to return a book after hours. She was on her cellphone with her best friend, Rachel, who suddenly heard Queena scream-and then the line went dead.

In 2006, Elizabeth Shoaf was abducted near her rural South Carolina home. The teenager was missing for over a week, when a text message came through that infused hope into the case.

After TikTok influencer Nikki Kuhnhausen vanished, her friends, family and transgender allies across Vancouver demanded justice. Nikki's family describes the brave 17-year-old and how police used her Snapchat account to find her.

When Becky Koster returned home from a night out, she texted her mother Barbara that she made it back safely. But, when Barbara arrived home hours later, Becky was nowhere to be found.

The family of Kenia Monge share the agonizing details of what happened around the 19-year-old's disappearance. Father Tony Lee, her sister, Kim, and authorities explain how the texts in Kenia's cell phone were the impetus to finding her abductor.

Iowa home-baker Justina Rucinski had just received an email with the largest cookie request of her career. But when the customer arrived at Justina's house to leave the deposit, Justina was brutally attacked and taken away at gunpoint.

Hannah Anderson's best friend knew something was wrong when Hannah stopped responding to her texts. Hear the harrowing saga around Hannah's kidnapping and how the amber alert system was used for the first time.