Members - Half Life: Universal Disaster mod for Half-Life

You play as a scientist, working in a team of scientists, doing contract work for the government. Your team is working on teleportation technology, that uses an alien universe to work. This universe has it's own physics and is held together by an overlord. During one teleportation mission into the alien world a soldier kills an alien. This angers the overworld. He is going to destroy your universe to destroy the bond between his and yours. The government needs to cover all this up, invades your labratories and takes you into custody. Two of your colleagues could escape in time. Now you have to fight your way through the facilities to get to the big teleporter, to teleport into a different, nearly identical, universe, to save yourself and your two colleagues.