Drowning Doesn't Look Like Drowning (2021) (gcaptain.com)

That last line, "children playing in the water make noise. When they get quiet, you get to them and find out why."

fills me with dread.

As a summer lifeguard when I was younger, I agree with the premise - drowning doesn't look it. Each time I encountered it the key was someone simply staring at me - they don't raise their hands or call for help. It even happened once in my own home swimming pool when a pre-teen got in over his head. His parents definitely didn't notice. Except the very first time when I went over to see what the problem was I now extend a cleaning net to them - they grab on very fast and tightly.