While on the road, the band notices a break-in at a defense plant. The Hardys retrieve a map for their father and notice suspicious activity.
A Native American stranger brings a mystery to the Hardys' front door. The Hardys are tasked with scouting for a stolen viking artifact.
An encounter at the train station puts the Hardys in the middle of a counterfeiting conspiracy. The Hardys go up against the Miami Gang.
A prowler causes trouble at Captain Early's cabin. An imposter leaves a strange photo for the boys' father.
The band run into intruders at Wanda's uncle's cabin. Pete's cousin Bill needs help from the Hardys.
While boating at night, the Hardys are caught in another mystery. The sabotage of a bridge's construction has the band searching for a culprit.
The Case of "The Ghost at Skeleton Rock" and "The Mystery of the Chinese Junk".
"The Shore Road Mystery" and the case of "The Sign of the Crooked Arrow.
The Hardys are too late to stop a late-night thief. Chubby's heirlooms bring danger with them.
Rumors of a screaming witch intrigue the Hardys. The Hardys look for a stolen will that will determine a school's future.
The case of "The House on the Cliff" and the "Mystery of the Spiral Bridge".
The Hardys help Robbie after he's mysteriously attacked. After being outbid at an art auction, the Hardys become involved in a treasure hunt.
The Hardys are run off the road while going to a derby. A trip to Rio De Paulo puts the band in conflict with gangsters.
Thieves keep stealing secret scientific formulas. The Hardys must solve the disappearance of a criminal informant.
The band finds a mystery in a set of museum bones while looking for Professor Mills. While taking part in a regatta, the band stumble on an aquatic mystery.
The Hardys can't find an Indian prince they are suppose to escort. The Hardys spy on a gang communicating through short wave radios.
The band must solve a mystery after a failed stakeout. A brazen robbery puts the Hardys back in action.