3 slow moving lights, very low altitude, no sound, watched them approach, watch them going away, no recall of them overhead.On business for 2 weeks, had AirBnB place on Fripp Island. Went to the beach each evening to watch the sun set and moon rise. Was out especially late this evening standing in the dune area watch the ocean. Looked north and noticed 3 lights, two smaller, one larger in the middle, it appeared more forward of the other two. They were stationary for an extended period, the lights were being switched off, then on, individually, slowly. I thought it was associated with the Marine Air Station, or the Coast Guard, then I thought it may of been an in flight refueling. Then I realized they were just not going any where, when I also realized there was no sound. I started to get frightened and headed further into the dunes area, the lights all went out then went on again in a different formation and appeared to be moving. I ducked down behind a bush. I remember seeing them approach, they weren't high up, at all. The next thing I remember is me standing at the bush I ducked behind, looking south, at the same lights, without sound, moving slowly down the coast. I have no recall of them flying over me. They had to....This has been nagging at me since that day.