Friends of the Hardys
Chet, the Hardys' best friend, lives on a farm about a mile outside of Bayport. The pride of his life is an old yellow jalopy he nicknamed "Queen." Chet is rotund and freckle-faced, and loves to eat. Solving mysteries with the Hardys always gives him the jitters, but despite this, he is a loyal assistant and has often rescued them from dangerous predicaments. Chet is always picking up new hobbies, which sometimes play an instrumental part in solving a mystery.
Allen Hooper is a lanky, blond boy nicknamed Biff because of his fondness for a distant relative who is a boxer named Biff.
Of Italian descent, Tony is lively and has a good sense of humour. His boat, the Napoli, is a good ship, but not quite a match for the Hardys' speedboat, the Sleuth. Tony's father is a contractor.
Phil is a quiet, intelligent boy who, in the newer books, is a computer genius.
Jerry, an excellent fielder on Bayport High's baseball team, is of medium height, wiry, and strong.
Chet's sister is dark-haired and pretty. Joe Hardy thinks she is the nicest girl in Bayport High and dates her regularly. (Iola was killed by a terrorist car bomb that was meant for Frank and Joe in Casefiles #1.)
Callie is in Frank Hardy's class at Bayport High. Frank often dates the vivacious blonde, and likes her better than any other girl he knows.