Ο πρωταθλητής

Who is this dangerous and elusive stranger who enters Thanasis's life and causes him problems and adventures with his striking resemblance? Is he an agent of a foreign power? Is he a ruthless criminal? Is he someone who wants to destroy his happiness? Is he a common opportunist, or is he an alien? And what should Thanasis do to confront him and ultimately emerge as the "champion"?