However, Barnes later theorizes that the magma is still flowing underground through the Red Line subway extension, and calculates that the main eruption will occur at the end of the line at the Beverly Center near Cedars-Sinai. To prove this, Barnes and Roark lower a video camera into the tunnel to watch it, only for the camera to be incinerated by a fast-moving flow of lava. They calculate the speed and realize that they have thirty minutes until the lava flows reaches the end of the Red Line.