Joe Hardy

Fenton Hardy

Father and younger son, with Joe assisting Fenton alongside Frank in investigations.

Frank Hardy

Brothers and inseparable partners in sleuthing, with Frank often taking the lead.

Red Jackley

Joe joins Frank in chasing down Red Jackley, showing determination to catch the criminal.

Fenton Hardy

Father and younger son, with Joe assisting Fenton alongside Frank in investigations.

Red Jackley

Joe joins Frank in chasing down Red Jackley, showing determination to catch the criminal.

Frank Hardy

Brothers and inseparable partners in sleuthing, with Frank often taking the lead.

Frank Hardy

Brothers and inseparable partners in sleuthing, with Frank often taking the lead.

Fenton Hardy

Father and younger son, with Joe assisting Fenton alongside Frank in investigations.

The Speed Demon

The younger Hardy boy, fair-haired and fifteen, riding alongside Frank and eager for a real mystery.

The Stolen Roadster

Joe is quick to anger at the reckless driver and helps identify the wrecked car as the same one that nearly hit them.

III: Traces of the Thief

Accompanies Frank and Chet, theorizes the thief stole the car in a hurry.

IV: The Holdup

Joe supports Frank's line of questioning and expresses confidence that the thief and holdup man are the same person.

Chet's Auto Horn

Participates in the conversation with his father and watches Chet's prank.

VI: Tire Tracks

Discovers the distinctive tire tracks that lead to the recovery of Chet's roadster.

The Mansion Robbery

Eager to join the investigation; whispers skepticism about Applegate's accusations.

The Arrest

Joe offers consoling words to Perry and supports his brother in comforting the Robinson family.

IX: Red Hair

Assists Frank in examining the wreckage and is excited about the clue.

X: An Important Discovery

Shares Frank's enthusiasm for solving the case and joins in the search for clues in the woods.

Mr. Hardy Investigates

Excited about the clues, discusses strategy with Frank, and expresses determination to solve the Tower robbery.

XIII: In Poor Quarters

Joe shares Frank's anxiety about their father's delay and expresses doubt that even their father can solve the case.

XIV: Red Jackley

Impatient for news, joins Frank in questioning their father; expresses hope that Jackley might confess before dying.

The Chief Gets a Bomb

Suggests rounding up the gang for help; participates in the plan to delay the police.

A Confession

Excitedly proposes starting the search immediately to recover the treasure.

The Search of the Tower

Assists Frank in the search and suggests the loot might be in the new tower.

XVIII: The New Tower

Supports Frank's account and participates in the search of the new tower.

XIX: The Mystery Deepens

Supports Frank's account, defends Henry Robinson's honesty, and hopes the second search will vindicate them.

XX: The Flash in the Tower

Joe spots the flash of light in the tower and identifies Adelia Applegate searching with a flashlight.

A New Idea

Joe eagerly agrees to the outing, helps prepare lunch, and shares Frank's sudden insight about the old water tower as a possible hiding place.

The Search

Follows Frank eagerly, searches frantically through the junk, and is the first to pull out the gunny sack containing the treasure.

XXIII: Adelia Applegate’s Compliment

Present and impulsively slaps his knee when Mr. Robinson is reinstated; also receives a $500 reward.

The Last of the Tower Case

Shares Frank's level-headedness, looks forward to future mysteries, and enjoys the celebration.