Dr. Mona Barnett has invented a machine to travel back in time to recover historical artifacts thought to be lost forever. A malfunction in her machine while on a mission lands her in another time, past the formation of the earth itself, and stranded on another world where the dominant species isn't human. Mona finds herself in a fight for her life, for the life her new friends, and to find a way to get back to her own world in a broken machine.