This long short (it is half an hour long) is an excellent little mystery story by Doty Hobart and Kenean Buel, full of little surprises. First of all there is the initial double-take - a crook spies a man putting money into his safe and gets together a gang to do the burglary. But this is not what the film is about at all; it merely sets the scene. Second little surprise - one of the crooks is a woman (Alice Joyce). Since she is treated in a friendly fashion by the owner of the house (Tom Moore) who catches her in the act, she breaks with her two confederates. But in the middle of all this both the man and the woman-burglar faint (quite separately) and fall into a mysterious coma. Third little surprise, we see what appears to be a male black nurse in a private clinic treating white patients. The doctors are completely baffled by "the sleeping death" and call in an Indian hypnotist who, after examining them, recounts a legend that will explain the mystery. Fourth surprise - an no so little - as the story commences we have, just a few months after the film Cabiria had been shown in the US, a superb "Cabiria shot" (zooming in on the temple door). Segundo de Chomón, main cameraman for Pastrone's great epic in 1914, had introduced the use of a dolly to not merely produce lateral and vertical panoramas (which weer already in use) but also to provide movement of the camera towards and away from the scene which had very rarely been done before (there is an example in a 1913 film of Yevgeny Bauer) hence in the US it was known as "a Cabiria shot". This genuinely mobile use of the camera became very important in European film but remained (until very recent times) little used in the US where operators and directors were completely wedded to cross-cutting (which could provide a kind of illusion of mobility). However there are at least two examples I know of of Cabiria shots being used very effectively in US films at this time - and the use in Cabira is actually quite tentative: this is one and the other (even more radical) occurs in two places in Allan Dwan's 1915 film David Harum.
In the story within the story, African Americans are employed in more customary roles as servants to the bronzed-up white actors who play the upper-class Indians (the princess is Alice Joyce again) and the slave she falls in love with (Tom Moore again). So we have two parallel stories (one modern, one ancient) with the same actors of the kind that would later be used by Cecil B DeMille in the US and by Michael Curtiz (Mihály Kertész) in Austria and the US (in 1914 he was still in Hungary). And there is another little surprise here too. The story is not entirely told consecutively and there is a linking frame which constitutes a kind of flashback within the flashback, another very rare occurrence in early film (at least before Sjöström's Körkarlen in 1921).
The solution of the mystery I shall leave you to discover for yourselves.....