As you approach the bend in the corridor you hear from Sally again. She's back with you.

There is a frag grenade laying on the ground just in front of the next doorway. Exercise extreme caution. There are several aliens on the other side of the doorway, as well as a turret.

When you pass through the door, the turret is up to the left.

Once the room is cleared of hostiles you'll want to head out through the door on the far side of the room.

Proceed up the stairs and approach the doorway quietly.

There are two aliens in this room. Once you have defeated them both, the door on the far wall will open and Sally will come out.