As you head into this neutral area, you will encounter a general of the enemy forces accompanied by his bodyguard. They talk to you with the usual bluster, but they don't give you any useful information.
Continue running past them to door A. Inside, you will see a 1-Up doll in the upper-right corner. In order to reach it, you'll need to make use of the floating platform that moves back and forth in the room. Let it take you to the right, and grapple up to either platform on the right side. After you collect the doll, wait for the floating platform to start moving to the right, and then jump off. You should land on it before hitting the spikes.
Back outside, if you wish to continue exploring to the right, you will find that a metal wall has been erected that is impassable, but can be destroyed. Shooting the wall will trigger the alarm. It's possible to swing below the wall and reach door B without triggering the alert. If you do so, there is a soldier outside door B, who is astonished by your unexpected visit in the Japanese version, but tells you that Joe is in Area 7 in American version instead. The swing method works in both versions.
With whatever method to get pass the wall, head quickly to the right to door B. Inside, you will find the yellow communicator δ. It's situated in the upper right corner, and the method to collect it is identical to the method used to collect the 1-Up doll from behind door A. Although you won't be needing this communicator until you reach the three final areas, you might as well collect it now so that you don't have to return here later.
Once you exit the room, there is nothing left to do here, so leave this area as quickly as possible.
- As stated above, the metal wall will only disappear if you shoot with 3-way.
- There is no platform in room B, but a yellow spider instead.