Mark and Sarah have everything together. They have good grades, true love, and what appears to be a bright future. However, things aren't always what they seem. Mark finds a mysterious key on the ground and takes it, his parents simultaneously disappearing to an unknown location. They are nowhere to be found, and both Mark and Sarah are despondent, and terrified of what their fate may be. However, they unravel yet another piece of the puzzle. They key can travel to the future. Mark and Sarah figure out that they need different keys to travel to different places in time, and they battle against the clock until the very last minute, trying to save both Mark's parents' lives, and their own.