Or, in English: The Color (out of Space)
This 2010 German film is at its center a faithful retelling of HP Lovecraft’s novella, moved to a new setting: Germany just before World War II and just afterwards, with a more modern framing story.
I only know a handful of German words–the useful phrases that a tourist learns while traveling, and the useless ones picked up from WWII movies–but most of this story is told so clearly in visual images or adheres closely enough to Lovecraft’s familiar tale that I can follow most of it without turning on the subtitles.
Anyway, the first part is in English.
Old Dr. Davis has flown from the US to Frankfurt, then disappeared. His son Jonathan (who is supposed to be American, but I find his accent extremely suspect) goes to Germany to try and find him.
Before Jonathan leaves on his journey, he speaks to an old friend of his father’s at Miskatonic U, who recalls that Dad was stationed as an army medic at end of the War around Bavaria and Baden-Wurttemberg. Dr. Davis hadn’t visited Germany since then and has no other connection to that country, so this is the only clue Jonathan has as to where his father might’ve gone.
Arriving in Germany, he rents a car and drives around the Wurttemberg Forest area until he encounters a detour; an empty valley is being flooded to create a reservoir. The road that used to lead through it is already impassable under water. A narrow dirt road winds around the edge of the new lake. Jonathan takes this through the forest, stopping at one point to get out and look around. The water is visible through the trees.
There’s a feeling that something strange and unsettling is going on in this place: The wings on a dragonfly audibly snap shut when it lands on a leaf. A toad appears to be watching Jonathan from its hole.
What Jonathan doesn’t see before he gets back in his car is an American passport lying on ground not far from the road.