Lois is a smart, independent female adventurer and amateur detective from England, the daughter of a strong soldier named Captain Tom Cayley of the Forty-second Highlanders. After her father died, her mother married Colonel Watts-Morgan, who left behind considerable debt when he died. With no money left to her, Lois decides to travel the world and seek adventure, getting jobs along the way and thwarting evil doers that she comes across. She eventually returns to save her true love, Harold Tillington, from a diabolical plot.