An unpleasant scientist works in his home, which is peopled by employees and relatives whom he mistreats, and who hate him. When he is apparently slain by his own death trap, Charlie Chan (Sidney Toler) is on hand to investigate, assisted once again by one of his children (No. 4 son Eddie, played by Edwin Luke, brother of Keye Luke, who had formerly played No. 1 son Lee) as well as Birmingham Brown (Mantan Moreland). Al Bridges makes a good contribution as a wry sheriff, too, in one of the better entries in the Monogram series.

Recommended.