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.

Charles and Lizzie Peterson love puppies. They want a puppy of their own more than just about anything. They know dogs are a lot of work. But their Mom still doesn't think their family is ready for a puppy. Then, Goldie arrives. She is a sweet golden retriever who needs a home. Goldie is very young. She doesn't know how to be a good puppy yet. Will Charles and Lizzie be able to help her?

This time the mysterious box that Ranger the Golden retriever found transports him to a Maryland plantation before the Civil War, where he must help a young house slave named Sarah and her younger brother Jesse find their way to the underground railroad and North to freedom, before Jesse is sold to a plantation further South.

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--and when 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 the mysterious box transports the golden retriever Ranger back to the shipyards of Belfast in 1912, where a ship is being prepared for her maiden voyage, and when he saves young Patrick Murphy from being crushed by falling boards, Ranger expects to be transported home; when he is not, he knows that somehow his job is not finished--but then, Ranger has never heard of the Titanic, and knows nothing of the fate that awaits Patrick, and all...

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.

Once again the mysterious box takes the golden retriever Ranger back in time, and he finds himself on Robert Falcon Scott's ship, the Terra Nova, headed for Antarctica, where his mission is to save Jack Nin, a Chinese-Maori stowaway from New Zealand, from the blizzards, unstable ice, and the other hazards that lie ahead for the doomed expedition.