The poster comes from the collection of Dorothy Dietrich and Dick Brookz of the Houdini Museum in Scranton, who own a complete set of all 14 posters from the serial. The posters have remained private, not part of the museum display, and have only been shown to a handful of visitors.
"We have been offered in the range of $20,000-$30,000 each for several of them, and $195,000 for the entire set of 14," say Dorothy and Dick. "They are all kept in a safe deposit box in a secret location. We love having them. As much as it breaks our hearts to let any of it go, we need to raise funds."
David Haversat says the decision was made to go with Episode 3 because this particular poster has never come up for auction before. Here is the description from the not-yet-released auction catalog:
Lot 95. Houdini, Harry. The Master Mystery starring Harry Houdini (1919). Stone lithograph (Otis Litho- one sheet poster) for Episode Three. Very rare and desirable, only several known to be in existence. In original form, unmounted and in good condition. Small loss on left-hand side near border with original fold-lines. Very bright and clean. Your opportunity to own something very special. $22,000-$24,000
Haversat & Ewing's November 11-12 auction lots are not yet available to view online, but details and links will appear at their website (and on my Houdini Calendar).
Thanks to Dorothy and Dick for the news.
UPDATE: Master Mystery episode 3 poster sells for $28,080.