Watch An Air So Pure Full Movie Free Online 123Movies. In the midst of WW I, a doctor and a lawyer team up to turn a ramshackle old mountain chateau into a sanatorium/health spa that caters to the afflicted from most every stratum of European society, most of whom show up with false hope in their hearts and plenty of equally false identities. Even the proprietors have a few deceptions, chief among them is the part of the resort where they provide shelter for dying and horribly maimed soldiers. Still the atmosphere of this high-class convalescent home is that of great gentility that thinly disguises the seaminess of the guests' secret activities. Though much of the film is a quirky comedy, tragedy comes creeping in when people begin dying of unnatural causes, and not even the pure mountain air can save the owners and the residents.