the second film of the mr. wong series be a technically primitive and unimaginably dull and talky mystery . even the mystery itself doesn not stand up to much scrutiny this time ( spoiler represent what kind of killer would send a threatening note to his intend victim write on a piece of unique paper that can be trace directly back to him . ) . karloff presence notwithstanding and the entire film have only two interesting scene represent in one and a murder take place in front of at least ten people and yet nobody notice it at first and they go on play a guessing game a if nothing have happen while in the other and detective wong gather ( indirectly ) all the murder suspect in his house and explain his various theory in detail and in a sequence that play very much like an early version of all those and now all will be reveal . ending of the poirot movie . ( half ) .