Basset hound Barney is `top dog' at home, enjoying salmon and venison as some of his favourite treats. But lately Barney's vertebrae have been causing him problems and Noel Fitzpatrick needs to perform high-risk surgery using 3D-printed implants. The professor also treats a giant mastiff called Tank, who is suffering from severe arthritis and needs radical surgery on both elbows, and a family puppy who has fractured his foot jumping off a bed. Now he requires specially developed surgical treatment.