Heir is presumed dead but shows up alive then is killed.

Government agent Charlie Chan is investigating a spy ring intent on stealing radar plans, which leads him to a radio station in a building also containing a radar research facility. Stars: Sidney Toler, Mantan Moreland, Ben Carter, and Benson Fong Mantan Moreland and Ben Carter perform a version of their nightclub routine. A lack of a copyright notice in the film puts it in the public domain. IMDb Link

A mysterious Chinese woman arrives at Charlie Chan's home and is murdered there shortly afterward. The only clues are the ring with which she introduced herself, and the message "Capt K" she scrawled before dying. The screenplay for this movie is almost identical with that for Mr. Wong in Chinatown. Both were written by Scott Darling.

From IMDb: Two members of a show troupe are murdered, and Charlie Chan is called in to solve the case. Stars: Sidney Toler, Mantan Moreland, Victor Sen Young, Tanis Chandler, Larry Blake, Kirk Alyn, Rita Quigley, and Anne Nagel This is the last of twenty-two Charlie Chan movies starring Sidney Toler. This movie can also be found here.

This print is much sharper than the existing IA copy. Roland Winters as Charlie Chan uncovers dirty deeds and murder in an Arizona gold mine. Mantan Moreland and Sen Yung are on hand to hold flashlights. Directed by William Beaudine Released in 1948 a.k.a. "Charlie Chan in The Golden Eye" Complete print CAST NOTE: Sen Yung is billed as Victor Sen Young MANTAN MORELAND MOVIES AT IA: https://archive.org/post/1006776/the-mantan-moreland-list-update