John was a competent swimmer- not as strong as he had been before getting shot at, true, but strong enough. That being said, the water was deep and filled with tangling weeds that seemed to wrap around him as if following some kind of purpose as he swam to the surface, finally breaching it and sucking in a sharp breath. His clothing was heavy, dragging him down, and his leg- damn his leg- it was caught in something, and he couldn't seem to pull free.

"Sherlock- I'm fine," he spluttered, wiping the grime off his face as best he could. "Leg's-- there's something--"