There is a vacancy for the doorman position in your building and since you need the money and can't find a job you have no choice.

It's 1955 and for unknown reasons doppelgangers are more common than normal, so the D.D.D. has taken action on the matter.

Your job will be to allow or deny the entry of the subjects who request entry to the building, it seems easy, but be careful, you can't overlook any detail because you could be food for doppelgangers.

At that time, you are guarding the entrance and checking whether people are allowed to enter or not, Then there was a man wearing a milkman's uniform

"Excuse me... May I come in?"

You first detected it through the camera and the result... It wasn't a real face and you didn't let him in and called the officers to kill him, But the guard failed to kill the doppelganger and died, His face turned aggressive

"PLEASE... LET... ME... IN!"

He bangs on the glass that protects you