This film opens with veteran police officers Dan MacDowell (Ralph Lewis), and his son Jack MacDowell (Neil Hamilton) attending a ceremony.
 The event is celebrating the addition of a new airplane to the law enforcement group.
Jack MacDowell will become the police plane's first flying officer.
Also, participating in the celebration is Gwen O'Day (Dorothy Gulliver).
 She is the daughter of a wealthy jeweler named Howard O'Day (Fred Esmelton).
Gwen is chosen to christen the new police plane with a bottle of Champaign.
During the christening, Jack MacDowell develops a fascination for beautiful Gwen.
The feeling is mutual.
The celebration culminates with a review of the force.

After the conclusion of the ceremony, we find another major jewel robbery that has happened in the city.
We further discover that only O'Day's customers were the victims of burglaries.
Somehow, all the robberies trace back the O'Day jewelry store.
All the thieves remain unsolved.
Howard is determined to solve these crimes, but can't make any headway on his own.
Howard asks Jack MacDowell if he can do a police investigation the diamond thefts.
Gwen overhears her father's request and secretly asks if she can assist too.

Meanwhile, Dan MacDowell turns sixty-five.
Under police department regulations, this is the mandatory age of retirement from the police force.
Dan is forced to retire.
Even though he is retired, Dan still wants to be involved in law enforcement.
Howard O'Day gives Dan a security job at the jewelry store.
He is the new night watchman.

Jack and Gwen continue to hunt for clues about the jewel thefts.
In addition to his watchman duties, Dan MacDowell is also assisting in detective work.
After investigating several clues, Jack whittles his suspect list down to one man, Howard's business advisor, Robert Chandler, played by Nigel Barrie.
But Jack and Gwen still haven't gathered enough evidence to press charges.

Unbeknown to Jack and Gwen, Robert Chandler is the leader of a gang of jewel thieves.
 Other members of the group include Rose Fisher (Thelma Todd), O'Day's stenographer and Red (David Kirby) the store janitor.
They have a straightforward plan.
Steal from the jewelry store customer, then sell the jewels back to the store.

Jack and Gwen continue their investigation.
Then another burglary is carried out.
This time they rob the actual O'Day jewelry store of precious diamonds.
During the commission of the crime, Gwen discovers the thieves; they, in turn, lock her in the vault and set the building on fire.
The thieves make their escape and board a waiting plane.
They will make their escape in the air.

Jack catches wind of the robbery, but this time, he knows who did it.
Jack and his father rush to the police plane, jump in the cockpit, strap up and take to the air.
They give chase to the fugitive's plane.
After catching up with the criminals, a night aerial battle takes place.
When the smoke settles, the jewel thieves are rounded up and arrested.
We confirm Chandler is the leader of a gang of jewel thieves.

Jack MacDowell, the department's first aviator detective, has proven the worth of an airplane in law enforcement.
He becomes the shining example of the newest branch of the law - the Sky Cops.
Even though Dan MacDowell is Sixty-five, the department waives the mandatory retirement, and he is allowed to rejoin the force.
Jack is a hero and marries Gwen.
This film opens with veteran police officers Dan MacDowell (Ralph Lewis), and his son Jack MacDowell (Neil Hamilton) attending a ceremony.  The event is celebrating the addition of a new airplane to the law enforcement group. Jack MacDowell will become the police plane's first flying officer. Also, participating in the celebration is Gwen O'Day (Dorothy Gulliver).  She is the daughter of a wealthy jeweler named Howard O'Day (Fred Esmelton). Gwen is chosen to christen the new police plane with a bottle of Champaign. During the christening, Jack MacDowell develops a fascination for beautiful Gwen. The feeling is mutual. The celebration culminates with a review of the force.
After the conclusion of the ceremony, we find another major jewel robbery that has happened in the city. We further discover that only O'Day's customers were the victims of burglaries. Somehow, all the robberies trace back the O'Day jewelry store. All the thieves remain unsolved. Howard is determined to solve these crimes, but can't make any headway on his own. Howard asks Jack MacDowell if he can do a police investigation the diamond thefts. Gwen overhears her father's request and secretly asks if she can assist too.
Meanwhile, Dan MacDowell turns sixty-five. Under police department regulations, this is the mandatory age of retirement from the police force. Dan is forced to retire. Even though he is retired, Dan still wants to be involved in law enforcement. Howard O'Day gives Dan a security job at the jewelry store. He is the new night watchman.
Jack and Gwen continue to hunt for clues about the jewel thefts. In addition to his watchman duties, Dan MacDowell is also assisting in detective work. After investigating several clues, Jack whittles his suspect list down to one man, Howard's business advisor, Robert Chandler, played by Nigel Barrie. But Jack and Gwen still haven't gathered enough evidence to press charges.
Unbeknown to Jack and Gwen, Robert Chandler is the leader of a gang of jewel thieves.  Other members of the group include Rose Fisher (Thelma Todd), O'Day's stenographer and Red (David Kirby) the store janitor. They have a straightforward plan. Steal from the jewelry store customer, then sell the jewels back to the store.
Jack and Gwen continue their investigation. Then another burglary is carried out. This time they rob the actual O'Day jewelry store of precious diamonds. During the commission of the crime, Gwen discovers the thieves; they, in turn, lock her in the vault and set the building on fire. The thieves make their escape and board a waiting plane. They will make their escape in the air.
Jack catches wind of the robbery, but this time, he knows who did it. Jack and his father rush to the police plane, jump in the cockpit, strap up and take to the air. They give chase to the fugitive's plane. After catching up with the criminals, a night aerial battle takes place. When the smoke settles, the jewel thieves are rounded up and arrested. We confirm Chandler is the leader of a gang of jewel thieves.
Jack MacDowell, the department's first aviator detective, has proven the worth of an airplane in law enforcement. He becomes the shining example of the newest branch of the law - the Sky Cops. Even though Dan MacDowell is Sixty-five, the department waives the mandatory retirement, and he is allowed to rejoin the force. Jack is a hero and marries Gwen.
The Shield of Honor