Anyone else think it was funny...
That in this world of advanced technology, surveillance, genetic/biometric scanning and detection that Four walks up to the camouflage wall and that little flying drone starts scanning him only to let him through when it reads the ID card he has in his hand?
This wall isn't guarded by a retinal scan, a facial recognition scan, a handprint scan, a full-body biometric scan, a DNA scan... all you need is an ID card.