Diederich - The idea

Our horror movie Diederich, will be set in the present day in Lowestoft.
It is about a young couple who move into the area for a new start.
This house seems pretty normal, but its past goes back 70 years to the second world war where it was home to the british dugout, where all german soldiers and pilots were brought to be tortured for information, and then killed.
What the couple do not know is that Diederich, a german pilot who crash landed on enemy territory, is still trying to escape.
They recieve letters from the 1940s, which they do not read and just discard as junk.
After one night out, the couple return to the house to find all of the letters open, pinned up around the house. Creeped out by this, the man of the house runs over to the patio door and begins to tear them off, revealing the figure of Diederich, wearing a horrifying Gas mask and trench coat.
They flee from the room and go to hide up stairs, where they find the teddy bear (Featured in the trailer) hanging from the ceiling in a noose with one of the open letters in its hands. It reads... "I will escape you."
From then on, the couple battle for suvival from the scary figure, completely oblivious to the reasons any of this is happening, leaving the audience on edge the whole time.