Car thief in swimming trunks

I went swimming in the lake at 7:30 in the morning. When I do that, I park my car in a small parking lot a hundred meters from the jetty, undress down to my swimming trunks and a sweater, leave my belongings in the car, and walk down to the shore with only a basket containing a towel, another pair of swimming trunks to change into, and my car keys. Then I swim for 45 minutes, more or less alone in the water, and return. This time, when I