Alex, a dog trainer, considers dogs, her trusted companions, more reliable than people, a belief largely shaped by her father having abandoned her and her younger sister Sarah when they were children. Thus she chooses not to see that veterinarian Jacob, with who she volunteers at a dog shelter, is interested in her romantically, as she is not at all in the dating scene. Although initially reluctant due to the reason for the job, Alex is hired by advertising executive Simon who wants to become an instant dog person to impress his wannabe girlfriend, successful fashion designer Chloe, who dotes on her very anxious pet dog, also named Simon, who hasn't bonded with his human namesake. Alex is convinced by Sarah to take the job not so much to help a human but to help a dog, Simon the dog who probably has underlying reasons created by diva-ish Chloe as to his anxiousness. As Alex and Simon spend more and more time together, they start to form a bond, potentially romantic, which is only strengthened when Simon plays an active role in saving the shelter when it becomes threatened. In addition to Alex needing to get out of her mistrust of people, they may not be able to overcome the hurdles to that romantic relationship, either breaking out from the professional reason that brought them together in the first place, and/or getting over their respective perception of another more suitable person as a romantic partner in the other's life, namely Jacob and Chloe.