Betrayal and espionage abound as an experimental aircraft is readied for its maiden voyage.

The story is told in flashback. Backers want a gambler to marry a rich girl for her dowry.

A woman and her weakling brother inherit a mine. When the brother commits suicide the guide is accused of murder.

When a friend of Charlie’s is found kicked to death by his own race horse on board a Honolulu-bound liner, the detective discovers foul play and uncovers an international gambling…

Heidi is orphaned and her uncaring maternal Aunt Dete takes her to the mountains to live with her reclusive, grumpy paternal grandfather, Adolph Kramer. Heidi brings her grandfather back into…

Mr. Moto Heads to China on a quest for seven ancient scrolls that reveal the location of Genghis Khan’s tomb—a crypt filled with fabulous treasure! But Moto isn’t the only…

Charlie’s visit to Paris, ostensibly a vacation, is really a mission to investigate a bond-forgery racket. But his agent, apache dancer Nardi is killed before she can tell him much….

While investigating the theft of antiquities from an ancient tomb excavation , Charlie discovers that the body of the expedition’s leader concealed inside the mummy’s wrappings.