Robyn Stafford, a young American executive, takes a few days off traveling and hiking near the Welsh border. There she encounters a handsome young man on horseback, wearing a sword, plate armor and a surcoat, who confidently identifies himself as Edward Plantagenet, Earl of March, and asks directions to a nearby abbey. When three hostile knights and two dozen bowmen arrive, he sweeps her up in front of him and carries her off to safety, before turning back to valiantly fight off his enemies. Then, the immediate danger past, he returns and asks him to come and be his lady once he has beaten the king. After a parting kiss, he rides away, into the distant past, to the age of the War of the Roses.

Now, Robyn Stafford must find a way to leave the world of today for the fifteenth century, where she fell in love with a young knight.