The Echoes of a Cold War mission has a secret hidden locker where you unlock The Redeemer. This guide on How To Unlock Weapons Locker In Call Of Duty Black Ops: Cold War will tell you where you must go in order to find the key so you can unlock the weapons locker and find yourself the Redeemer pistol.
This is during the main story mission, Echoes of a Cold War. After a short while into the mission, when you fall and lose your weapons. You’re fighting through enemies with your knife trying to meet up with Woods. On the way to meeting up with Woods there is a small room that contains a weapons locker inside. The locker is locked, interacting with it does not unlock it and magically, you cannot use your lockpick here. The same lockpick you’ve used to pick locks all game. Anyway, let’s ignore wonderful game logic and find that key so you can unlock the locker.
How To Unlock Weapons Locker In Call Of Duty Black Ops: Cold War
Continue following the path past the locker room until you reach this area. You will be attacked by several guards as you reach this room.
As soon as you enter the room take a right and follow the corridor down.
At the end of the corridor you will see a small room with an orange desk chair and a large TV. Head inside that room.
There’s a small room at the back of this room with a desk and some communication equipment. You will find the key sitting on the desk. Simply pick up the key and return to the weapons locker.