The Cathedral is a 2002 animated short film (six minutes) from Poland, by Tomasz Baginski.
A man is walking on the surface of an alien planet—it's definitely an alien planet, since there's a whacking big binary planet orbiting the one he's on at very close range. As the second planet passes in front of the sun to and throws the man's planet into darkness, the man sees what appears to be a medieval-style cathedral. What the cathedral is doing on some alien planet is not explained, especially since the rest of the planet appears to be nothing but bare rock. In any case, the man enters the cathedral and finds that the pillars of the cathedral are actually tree-like objects growing up from the ground. And there are faces in the trees...
- Alien Sky: The presence of an enormous second planet or moon revolving around the planet the man is on immediately shows the setting to be somewhere in deep space.
- And I Must Scream: The man's fate, after branches burst from his chest and he becomes part of the newest column of the cathedral, while still alive.
- Creepy Cathedral: A cathedral, on some alien planet. Made from some sort of tree things which come directly out of the ground. And which have living human faces amongst the branches of the trees.
- Eerily Out-of-Place Object: What the hell is a cathedral doing on a bare rock somewhere in deep space?
- Light Is Not Good: The man enters the cathedral as the second planet passes in front of the sun and leaves the man in darkness. The reappearance of the sun after the planet passes by seems to trigger the man becoming part of the cathedral, as branches burst from his chest almost immediately after the light returns.
- Silence Is Golden: No dialogue.
- Tidally Locked Planet: In any system where a smaller space rock was that close to a bigger space rock, you would expect the smaller one to be tidally locked, and in fact the lava planet that is orbiting the man's bare rock planet doesn't appear to be spinning. (Given how close the two are it would probably be more realistic to have the planets locked to each other, which would mean neither would ever appear to move in the other's sky.)