The only entry in the entire series in which both sons number one (Keye Luke) and number two (Victor Sen Yung) actually appear together.
Keye Luke returns to the series after an absence of 11 years. His last Chan entry was Warner Oland's last, Charlie Chan at Monte Carlo (1937). The last time he played Lee Chan was in 1938's Mr. Moto's Gamble (1938) opposite Peter Lorre, which was intended as a Chan picture, before Oland's absence forced the studio to hurriedly rewrite the script as a Moto feature.
Keye Luke, who plays number one son Lee, was actually older than Roland Winters who plays his father Charlie Chan.
Victor Sen Yung bows out of the series with this film, after a total of 18 entries, playing number two son Jimmy (Tommy in the Monograms). He was introduced in Charlie Chan in Honolulu (1938). Sidney Toler's debut as Chan, to replace the absent Keye Luke.
Writer Oliver Drake's plot was actually lifted and updated from his 1937 Three Mesquiteers Western, "Riders of the Whistling Skull."