Kelly gets admitted into a rehab center and meets her mysterious new roommate Tara Marks. While Kelly is away, Colin and Valerie keep each other company, while romance grows on their minds. Donna investigates a new cardiac procedure that could help Joe. Meanwhile, the gang goes to Mammoth Mountain for a ski weekend where Brandon and Susan get stranded on the mountain in a blizzard, and David gets introduced to two girls at the ski lodge with the same name of Mary.