Two children of an American millionaire are sent to "Ireland" (quite cleaerly not filmed on location - despite the clever attempt to put a kildare numberplate on an american limousine) to stay with their new step-mother...Ethel and Tommy Barrick are sent to Ireland to spend the summer with their new stepmother. Once there, they discover her to be an evil, power-seeking witch, with real magical powers and a hatred for all things green.