The British Film Institute tells us: “Sadly, the second half of this episode no longer exists”.
Adapted from chapter 4 of The Mystery of Dr. Fu Manchu (UK)/The Insidious Dr. Fu-Manchu (US) (1913), the first novel in the Dr. Fu Manchu series. The story is developed and resolved in Chapters 4-6, which are posted here for those curious to know what happens next.
Online: Internet Archive
Contents
Episode 1: The Scented Envelopes [Lost film. The “scented envelopes” case is the short story The Zayat Kiss, “The first of the great struggles between Nayland Smith and the sinister Fu-Manchu” - a helpful introduction to the series.]
Episode 3: The Clue Of The Pigtail
Episode 9: Aaron's Rod [Currently unavailable, first reel missing. The “Aaron's rod” case is in chapters 7-10 of The Devil Doctor (UK)/The Return of Dr Fu-Manchu (US) (1916), the second novel in the Dr. Fu Manchu series. ]