When you finaly make it to the second lab you notice that there are no scientist to be found.
The lab itself also looks way different than the first one.
It looks WAY older and more run down.
Eventualy you find a group of scientists and security gaurds who have set up a little base of operation near the portal by baricading the doors.
One of the scientist says that he got a message from another scientist that you were comming and that they already started prepairing stuff for your mission.
He tells you that you need to go into the alien dimension and kill the alien keeping the portal open. He also says that when you kill the alien that the portal will start to slowly close so you need to get back to the portal as fast as posible. Or else you are stuck in this alien dimension.
He says that they have been trying to close the portal but they couldnt because there where to many aliens comming out of the portal. So they need your help to fight off the aliens comming out of the portal while they try to shut it down. So then you fight off monsters togheter with the security gaurds while the scientists try to close the portal.
Appearance description here.