Zosia arrives at Holby keen to get back working on Darwin. With her knack for irritating Jac in full swing, will Jac be able to track down Frieda before Zosia gets too comfortable? Ange struggles with Holly's parents who are intent on fighting for their daughter. When an offer of hope for radical treatment comes from America, Ange does her best to make them see what is really best for their daughter. Donna and Xavier struggle to keep their domestic arguments at home - will being forced to work closely together for the day sort out their differences or drive them further apart?