The plot centers on Sidney Toler’s portrayal of “Charlie,” accompanied by his son "Tommy" (Benson Fong) and chauffeur "Birmingham Brown" (Mantan Moreland), as they look into a bank-related murder involving three people. A peculiar element arises from the use of cobra venom in the killings, which brings back memories for the detective of an earlier case he handled in Shanghai. The individual responsible for that prior crime managed to flee despite suffering severe burns—and “Chan” believes this person might be repeating their offenses. However, the extensive damage to their face required reconstructive surgery, meaning their current appearance is unknown! This installment leans more heavily on Moreland’s comedic routines than typically seen; the underlying mystery feels somewhat formulaic, and the frequent missteps of No. 3 son occasionally become tiresome. Nevertheless, a significant portion of the story unfolds beneath the surface—creating an unsettling atmosphere—and there's enough to keep one entertained for about an hour. It isn’t among the strongest entries in the series, but it remains acceptable.

Source on TMDB