people have reached 911, and emergency vehicles are on their way. >> they need to take his clothes off. >> they're putting blankets on them. >> right now. >> sienna, we got a blanket. we have a blanket in the car. i don't know if they need one. >> a crowd surrounds the men. they remove their cold, wet clothes and cover them with blankets and coats. one man takes off his own shirt to provide body heat it one of the men submerged the longest. >> at that point, i turned the videocamera off. i don't need to be in the guy's face when he's suffering. >> everyone survives the incident, but the lake is closed for the rest of the winter. >> i think it really took seeing it happen, as it -- play out in front of your eyes to see how dangerous it is. oh. coming up -- another high-stakes rescue attempt on thin ice, and this time it's a stranded best friend. >> hey, chloe. you're just afraid that just can't get close enough fast enough.