Once upon a time a man who had become invisible arrived in America. An unlikely and unforgettable hero, Leo Gursky is a survivor -- of war, of love, and of loneliness. A retired locksmith, Leo does his best to get by. He measures the passage of days by the nightly arrival of the delivery boy from the Chinese restaurant and has arranged a code with his upstairs neighbor: Three taps on the radiator means, Are you alive?, two means YES, one NO.But it wasn't always so. Sixty years earlier, before he fled Poland for New York, Leo met a girl named Alma and fell in love. He wrote a book and named the character in it after his beloved. Years passed, lives changed, and unbeknownst to Leo, the book survived. And it provides Leo -- in the eighth decade of his life -- with a link to the son he's never known.