It was December 18, one day before Andrea’s and Mark’s Christmas vacation in Paris. She was working late again while her colleagues were having fun at the annual Christmas party. It was 12:15 a.m., and she was supposed to be drinking and chatting with her co-workers, but she had to complete her month-end report. Suddenly, Andrea’s office door opened. She looked up and smiled at the figure standing in front of her. It was...