During World War I, young Londoner Tom Grattan is sent to live with relatives in rural Yorkshire, where he becomes involved in espionage, sabotage, and other wartime adventures with local friends, facing threats like spies and German POWs.
A birthday letter from Tom's father is stolen and a dangerous paper chase ensues.
Tom and Julie are captured by sinister saboteurs with a plan to blow up a troop train.
Tom is caught up in a gun battle between soldiers and saboteurs.
Tom suspects that a Regimental Sergeant Major's grandson fears becoming a soldier.
Tom finally learns the truth about Christopher's 'cowardice'.
A German POW is shot. Should Tom reveal what he knows to the authorities?
A man who has lost his only son in France plans a terrible fate for Germans working at the quarry.
Tom wants to help a shell-shocked soldier recover his memory - but how?
Tom's new friend turns out to be a rich lord as two tinkers are pleased to learn
Tom has a spookily original plan to help rescue Lord Beck from his kidnappers.
In the dark cellars of a nearby castle, an inventor is working on a new weapon
Tom and Julie are trapped in the castle dungeons, and Stan has a hair-raising trip!
Tom embarks on a dramatic airborne chase when Julie is captured by German agents.