A man just graduated from college and a young widow, Mrs. Abel, swim together at night, making their way across miles of open lake. The meaning behind these night swims and the narrator's relationship to Mrs. Abel become increasingly clouded as the summer passes, until the night Mrs. Abel disappears. Twenty years later, the man brings his wife and two daughters back to the peninsula, attempting to understand his past. As he rebuilds a world he's lost with decades' old relics, he searches for clues to the fate of Mrs. Abel and begins to swim long distances in dark water once again.