Football season is in full swing, but this year there's a parallel drama being played out far from the action on the field.
An investigation into the effects of concussion and repeated head injuries to football players may rock the very foundations of the sport. The Frontline documentary, "League of Denial" looks at the NFL's response to increasing evidence that repeated head injury puts players at risk for degenerative brain diseases.
In San Diego, we've felt the shock of losing Chargers' great Junior Seau to suicide. It was found that Seau was suffering from chronic brain injury.
Prior to tonight's showing of the controversial documentary, we hear from Frontline producer Jim Gilmore and Dr. Alexander Khalessi, UC San Diego director of endovascular neurosurgery and surgical director of NeuroCritical Care.