When Zack Clements of Brownwood, TX, was 17, he collapsed while running during gym class and went into cardiac arrest.

In the blink of an eye, the teenager went from being an active, healthy, and normal athlete at Victory Life Academy to laying lifelessly on the ground.

For 20 minutes, Zack had no pulse and was “legally” dead. But then something happened that many people still cannot medically or scientifically explain.

Zack’s pulse suddenly returned to normal and he was revived. Three days later, he awoke at Children’s Medical Center in Fort Worth, TX, with no lasting effects from his terrifying ordeal.

As if that wasn’t unbelievable enough, it’s what the teenager said when he woke up three days later at the hospital that made his story to go viral.

His parents, Billy and Theresa, were so surprised by their son’s admission that they videotaped him recounting what he saw during those 20 minutes he went without a pulse.