Just over a year old, Labrador Charlie is already living on borrowed time. An aggressive cancerous tumor is eating away part of his front leg and his only chance of survival is a bionic appendage that exactly mirrors his diseased bone. The challenge to Dr. Noel Fitzpatrick is enormous, and across the hall, senior surgeon Michael Hamilton faces an equally large task. Tiny chinchilla, Zippy has broken both of his arms. Can Michael come up with an ingenious solution to secure them back together?