미국인 의사 벤 맥케나와 조 부부는 아들 행크와 함께 프랑스령 모로코로 휴가를 즐기러 간다. 그들이 시장에서 쇼핑을 하고 있을 때 한 아랍인이 등에 칼을 맞은 채 그들 앞에 쓰러진다. 그는 벤에게 암브로스 채플이라는 말 한마디를 남긴채 죽고 어린 아들은 누군가에 의해 납치당한다. 아들을 구하러 나선 맥케나 부부는 추적끝에 국제 스파이 조직이 런던의 앨버트 홀에서 외교관을 암살할 계획임을 알아낸다. 교향악단의 연주가 시작되고 암살의 신호인 심벌즈가 울리기 직전 맥케나 부부의 노력으로 외교관의 암살은 저지되고 그들은 아들을 스파이 조직으로부터 구해낸다.
When a cold medicine causes Sach to be able to smell diamonds, he and the rest of the Bowery Boys are induced by a diamond dealer to accompany him to Darkest Africa in search of a legendary cache of them.
The Randolph family have a tradition of working in the British colonial service. Clive comes home from a mission in the Gold Coast of Africa accompanied by his wife Helen. He discovers his younger brother John, is not keen on following in his footsteps. John is then persuaded to try colonial service by his grandfather. He is accompanied by Clive who has been sent to investigate the source of a series of radio broadcasts that are sewing unrest throughout the world. These may be linked to Hugo Zurof, a man plotting to rule the world.
Two boys – the prince Edward and the pauper Tom – are born on the same day. Years later, when young teenage Tom sneaks into the palace garden, he meets the prince. They change clothes with one another before the guards discover them and throw out the prince thinking he's the urchin. No one believes them when they try to tell the truth about which is which. Soon after, the old king dies and the prince will inherit the throne.
Captain Bob Hayworth, his brother Lieutenant Gilroy Hayworth and Captain Derek Marbury are in a World-War 1 trench on the front-lines in France. Bob Hayworth resents Marbury greatly as the latter had married the girl, Lucy Neville, Marbury was courting in pre-war London. Ordered to go on a night patrol, the cowardly Gilroy committed suicide rather than face his fear. Bob and Derek arrange it to appear that Bob had been killed by a shell-burst, and Derek, with his face camouflaged, takes the patrol posing as Gilroy. While on patrol, Derek is hit by a shell-burst and found by the German Red Cross, who turn him over to a family of French peasants.
