Catherine Tate's Nan makes life hard for Holby City surgeons and nurses when she is admitted to one of the hospital's wards. Catherine Tate's Nan makes life hard for Holby City surgeons and nurses when she is admitted to one of the hospital's wards. Catherine Tate's Nan makes life hard for Holby City surgeons and nurses when she is admitted to one of the hospital's wards. Catherine Tate's Nan makes life hard for Holby City surgeons and nurses when she is admitted to one of the hospital's wards.