The Distillery Reserve Key is a key in Dishonored
Distillery Reserve Key
Distillery Reserve Key Needed to open unbreakable door at the base of a set of stairs in the Old Dunwall Distillery. On the other side of the door is a red sofa with a bone charm on it.
Where to find Distillery Reserve Key
In the Old Dunwall Distillery Control Room (The room on top floor with desk and cell near it), turn the red Crank Wheel:
Then run and slide under the door (or you can use Blink to quickly move to the other side of the door) and find a small room with some lockers. The key is in one of the lockers. See screenshot for the Distillery Reserve Key Location:
ALTERNATIVE: One of the guards in the Dunwall Distillery has the key. You can choke out or kill the guard and then loot the key from its corpse.
ALTERNATIVE: Look above where the red distillery crank wheel is located, up to the two open window frames. Blink up onto one of them and into the room. To get out, do the same thing from inside the room. (This is how I did it.)
How to get out of the room
Climb crates on the corner and climb/jump out to the exit. Then go down to the unbreakable door and unlock it and get bone charm from red couch.