Who doesn`t enjoy a good mystery? You can score a free mystery gift card for Century 21 Department Stores (also know as C21 Stores)! Submit your email address and check your inbox for your free mystery gift card number. Gift cards will be valued between $5 - $500! To check your balance, add something to your cart on the C21stores website and at checkout enter your mystery gift card number (you don`t have to checkout since you`re just checking the balance). Available while supplies lasts!