''Heart of Glass'' (Herz aus Glas) is a 1976 film by Creator/WernerHerzog. One of his weirder ones.

A small town in the forest regions of Bavaria, late 18th century. The local economy is based on glassmaking--especially on the glass factory's one exclusive specialty product and moneymaker, the brilliant red "ruby glass". But when the foreman of the factory dies suddenly without having initiated anyone else to the secret formula, nobody is able to recreate the red glass. The factory is in decline, and with it, the whole town falls into despair.

Hias, a cowherd who has the reputation of a clairvoyant, leads a solitary life in the forests. The young baron, owner of the glass factory, obsessed with the lost secret and spiralling into madness, turns to him for help--hoping that Hias' psychic powers can recover the recipe.

But that isn't weird. What is weird is that Hias receives visions and makes long prophetic monologues that may or may not predict 19th and 20th (or 21st?) century history, and that all people except Hias and the glassmakers act as if they were hypnotized. In fact, says Werner Herzog, they ''were'' hypnotized. Why Hias wrestles with an invisible bear near the end is anyone's guess.

!! ''Heart of Glass'' contains examples of:

* AllThereInTheManual: The film is loosely based on a historical novel where much of what is cryptic in the movie had a perfect explanation. The book also revealed the secret ingredient of ruby glass; it is [[spoiler:gold.]][[note]]Which is not actually the real way in which ruby glass is made, which requires [[http://en.wikipedia.org/wiki/Gold%28III%29_oxide gold oxide.]] [[/note]]
* BlackComedy: Some think the movie should be considered an absurd black comedy.
* TheCaligula: The baron. While he's not an actual ruler, the entire community depends on his glass factory, and his growing insanity, seemingly harmless at first, gets more and more dangerous.
* TheCassandra: Hias in a nutshell.
* CassandraDidIt: When, true to Hias' prophecy, [[spoiler:the factory burns down]], the reaction of the townsfolk is to blame Hias.
* CreatorCameo: One of the workers that carry ruby glass into the mountains is Werner Herzog.
* CreatorThumbprint: For a change, ''Heart of Glass'' is a Werner Herzog movie that doesn't have recurring appearances and long close-up shots of a chicken. It's a duck this time.
* TheDeadCanDance: Invoked when [[spoiler:Wudy dances with the corpse of Ascherl.]]
* DepravedDwarf: Adalbert, the baron's morbid midget butler, seems like a harmless YesMan at first until it seems he was in on the baron's plan [[spoiler:to murder Ludmilla.]] Then again, maybe he is [[SplitPersonality just crazy]].
* DissonantLaughter: The old baron laughs continually for no apparent reason.
* DoomedExpedition: The four adventurous islanders who row out into the open ocean to find the end of the world in Hias' last vision.
* DyingTown: The town is on the verge of becoming one.
* FanDisservice: Think a young woman dancing topless on a tavern table is hot? Think again.
* LaughingMad: The either senile or crazy old baron and his continual laughter.
* MacGuffin: The lost formula for ruby glass.
* TheOmniscient: Hias borders on this--his non-stop prophecies always come true. Ironically, the one thing he ''doesn't'' see in his visions is [[spoiler:the secret of ruby glass.]]
* OnlySaneMan: Hias is the only one that doesn't behave like a sleepwalker (the actor was the only one not hypnotized). Also, despite his visions and monologues, he is arguably the most intelligent and reasonable person in the community.
* ThePiratesWhoDontDoAnything: Hias is introduced as a cowherd. Yet, we see him around cattle ''only'' in the very first scene. The rest of the movie he just sits around monologizing in the forest or the pub, hangs around the town making prophecies, and never does anything that looks like cowherding.
* PlotTriggeringDeath: The death of the foreman glassmaker Mühlbeck (who is never seen).
* RuleOfCool: When the baron wants the last remaining ruby glass destroyed, he orders the workers to lug it up a mountain and sink it into a mountain lake. It would be much easier to just crush it on the spot, but that wouldn't be as awe-inspiring.
* SanitySlippage: With bankruptcy impending, the baron loses his grip on sanity (though he was unhealthily obsessed with ruby glass to begin with). Special mention to him ripping apart the foreman's couch because he believes the stuffing is a coded message.
* SceneryPorn: In ample amounts, especially in the very first shots, and a long segment in the middle.
* StylisticSuck: Most of the performers were no trained actors to begin with, and were hypnotized on top of that. In a nutshell, they don't act at all, just sort of sleepwalk through the scenes and zombie-like deliver their lines. Of course, this is all part of the film's concept. Does it work? You decide.
* TakeOurWordForIt: There is a dangerous bear around which is a threat to the cattle, and Hias kills it with his knife in close combat. Really.
* TitleDrop: "I like you. You've got a heart of glass."
* YesMan: Adalbert to his master, the baron. Also a lot of the townsfolk and workers who never question the baron's orders even if they are clearly demented.
* YouCantFightFate: Hias predicts that Wudy and Ascherl (the two bar patrons) will get plastered beyond senses, therefore go to sleep on a hayloft, fall down from the loft, with Ascherl breaking his neck and Wudy surviving because he fell on top of Ascherl. They know. They talk about it. They get plastered beyond senses, go to sleep on a hayloft, fall down from the loft, with Ascherl breaking his neck and Wudy surviving because he fell on top of Ascherl. Truly a Greek tragedy.
* WhatCouldHaveBeen: At one time, Herzog planned to appear himself at the start of the movie and hypnotize the audience from screen.
* WhileRomeBurns: The hurdy-gurdy man keeps playing and singing while [[spoiler:the factory burns.]]