Charlie Chan in the Secret Service

Charlie Chan in the Secret Service was released by Monogram Pictures in 1944. Under the Copyright Act of 1909, works published between 1928 and 1963 required a copyright renewal filing in the 28th year of their first term to maintain protection. For a 1944 film, a renewal application should have been filed between late 1971 and 1972. A search of the Stanford Copyright Renewal Database and the Library of Congress Catalog of Copyright Entries (CCE) reveals no renewal registration for this specific title. While the 20th Century Fox Charlie Chan films were generally renewed, the subsequent series produced by Monogram Pictures, including this title, frequently fell into the public domain due to the studio's failure to file renewal paperwork. Commercial availability of the film in numerous 'public domain' box sets from distributors like Alpha Video and its presence on archive.org without copyright challenges further support this status. The user's mention of a 'colorized' version does not change the underlying status of the 1944 film. While the specific colorization process might theoretically create a derivative copyright in the color layers themselves, the underlying 1944 motion picture (the cinematography, script, and performances) remains in the public domain.