The mysterious box that Ranger the golden retriever found in the garden transports him back to first century Rome, where he must rescue Marcus, a young servant boy, and Quintus, a volunteer gladiator, from the brutal world of the Colosseum.

Ranger, the time-traveling golden retriever, has landed in Viking age Iceland, where he meets a girl named Helga, who seems perfectly able to take care of herself--until an erupting volcano and an early arriving baby forces Ranger and Helga to journey through the ash and smoke to find her father and bring him home.

When the mysterious first aid kit takes golden retriever Ranger to New Orleans shortly before Hurricane Katrina hits, he finds himself helping Clare Porter and her grandmother, who are waiting for Clare's father at their home in the Lower Ninth Ward--andwhen the levees break and Clare is separated from Nana, Ranger must somehow get her to the relative safety of the Superdome, and reunite her with her family.

This time Ranger, the time-traveling Golden retriever, finds himself in San Francisco in the middle of the great 1906 earthquake, and his mission is obviously to get a young Chinese immigrant, Lily Chen, to safety, but as they make their way through the ruined and burning city Ranger finds that he must also accomplish something else--finding Lily, who was sold as a servant by her parents, a new family who will care for her.