Worthington is the English chauffeur who drove the The Three Investigators in the Rolls-Roys sedan that Jupiter Jones had won in a contest organised by Rent-'n'-Ride Auto Rental Company, for a month. From the time the sleuths and Worthington met, they took an immediate liking to him to each other. As he had stated right when he started "serving" them, he appreciated being part of their investigations and their youthfullness and adventurousness, rather than "serving elderly and cautious people".
Throughout the series, he also, occasionally, abandoned the sedan, if a problem had befallen the sleuths, or if they had been trapped. It is known that Worthington is six feet and two inches tall. He is also often referred to as the Fourth Investigator by the sleuths.