This short (11 minutes) feature was suggested by Poe's "A Cask of Amontillado," or by "La Grande Breteche" by Balzac, or perhaps by both, or maybe neither -- sources (i.e., guesses) differ.
Arthur V. Johnson (1976-1916; he died less than three weeks before his 40th birthday) was a popular actor who appeared in over 325 silent films from 1905 to 1915. In this film he plays the king of an undisclosed country in an undisclosed time. His love interest (His queen? His mistress? Who knows?) is played by 27-year-old Sarah Bernhardt lookalike Marion Leonard, whose career of over 200 films spanned from 1908 to 1915.
The king, desiring some alone time with his love, seals off a section of the castle to give them privacy, leaving only one entrance. What the king does not realize is that his gal has been canoodling with the court musician (played by Henry B. Warthall) while he's away. (Warthall was a respected stage actor before he entered films. Among the 325-plus films he appeared in were THE BIRTH OF A NATION, WINGS, AFTER MIDNIGHT, and THE DEVIL DOLL; he had been cast to play the High Lama in 1937's LOST HORIZON, but died shortly before filming began.)
While the queen/mistress/whatever and the court musician are dallying in the private room, the king realizes he has been cuckolded. He orders the room sealed. (The illicit lovers are too wrapped up in each other to notice -- or even hear -- the masons who seal them up.) Too late they realize their fate and die from a lack of air in record time, all the while he king laughs and gloats outside their make-shift tomb.
As plots go, it's pretty straightforward. (Sorry if I spoiled the ending with the above description.)
Directed by D. W. Griffith and written by Frank E. Woods, the film features the single-camera work of G. W. Bitzer.
Look closely and you'll see Mary Pickford as one of the three ladies-in-waiting and Mack Sennett as a soldier.