Lara is an agent for the British Secret Service.
She had no last name, at least not at first, though later when she goes to live with the Cook family it would not be unreasonable to say her name was then Lara Cook. Neither would it be important to most people since Lara is a dog.
Here is where I tell you that the name Lara was selected as her name because her name tag says so - LARA. Of course, that tag does not mention that the name is really an acronym standing for Licensed Assault and Rescue Animal. In truth, she really "didn't have a name, just a reference number, GM451, given to her by the British government".
This outwardly cuddly mongrel was, in fact, a highly trained special agent, bred by the British Secret Service for use on dangerous missions throughout the world.
She came to be in a kennel looking for a home because in her previous mission, she had been captured by a bad guy and finally gotten free. Her training said "if separated from her handlers, she had to pretend to be a normal dog, allow herself to be captured by the RSPCA and secure herself a nice home with a family. She should simply melt into the background and wait for the Secret Service to track her down."
That nice home, she decided, would be with the Cook family who become a major factor to the adventures of Lara since she quickly comes to love them - and they her - and protecting them becomes almost as important to her as whatever mission she is given or decides on her own to do. The Cooks consist of Mum and Dad and their three young children, Ben, Sophie, and Ollie.
Lara is a pretty remarkable spy dog. She can understand several languages besides Dog. English, of course. And Advanced Cat and Basic Dolphin are a couple more. She is an ace surfer and a champion juggler (really!). She can also play cricket.
And she goes after bad guys out to harm her country.