Mothership Zeta ( add - on ) Mothership Zeta is the fifth and final add - on for " Fallout 3 " , developed and published by Bethesda Softworks . Release and availability . " Mothership Zeta " was initially released exclusively as downloadable content on Xbox Live and Games for Windows Live on August 3 , 2009 . It was made available for the PlayStation Store on October 8 , 2009 . For Xbox 360 , download codes for Xbox Live are also available in retail . Like all add - ons , it is included in the " Fallout 3 : Game of the Year Edition " , released on October 13 , 2009 for all platforms . For Steam users , " Mothership Zeta " , along with all the other " Fallout 3 " add - ons , is available , released on July 16 , 2010 . Overview . In " Mothership Zeta " , an alien mothership abducts the Lone Wanderer , making the whole add - on take place onboard the alien ship in orbit around Earth . Aboard the Mothership , the quest line is not completely linear and features some exploration . The Lone Wanderer will walk outside the ship into space and meet other abductees whom the aliens have captured over time . The player character is able to return to the ship and use it as a " home - base " of sorts once the main quest is completed , although most of the ship will become inaccessible . Story . The Lone Wanderer receives an unintelligible radio transmission which leads to a crashed alien recon craft . On approaching the wreckage , the player character is beamed into the alien mothership known as " Zeta " , where they will meet other prisoners who have also been abducted over the centuries . In order to escape , working together will be essential . After being beamed aboard , the Lone Wanderer is subjected to an alien medical experiment . In the cutscene , the player character passes out during the procedure and awakes in a cell with another abductee named Somah . She explains that all of their equipment has been taken . She comes up with a plan of escape : Staging a fistfight so that the alien guards will intervene , then overpowering them . They soon come across Sally , a little girl who was abducted soon after the Great War , who asks them to help her escape by destroying the reactor in the room . After freeing her , she says that she knows a lot about the ship and will provide aid in turn . Sally leads the Lone Wanderer to a room with several cryo - tubes , to acquire a spacesuit from one of the frozen abductees , an astronaut ( who , unfortunately , does not survive the " thawing " procedure ) . The suit is needed for a spacewalk outside the ship to access a teleporter ; first , however , the generators in three other areas of the ship must be destroyed in order to provide a distraction . Three of the abductees will offer to assist in each of the generator areas : Elliott Tercorien will help with the Cryo Labs , Somah will aid traversing the Robotics Factory , and Paulson will aid with the Hangar . After enabling the teleporter , the survivors are beamed to the upper section of the Mothership , where they witness a demonstration of the ship ' s Death Ray as a threat to scare them into surrendering . The player character must then fight through several portions of the second section which consists of a weapons laboratory , biological experimentation lab , and Biological Research . At the conclusion of this journey , all surviving companions can again join the Lone Wanderer by means of the transporter from the Observation Deck . After fighting through to the Death Ray control center , then the living quarters , the bridge is finally accessible . There , all of the abductees must defend the bridge from aliens attempting to re - take it , while at the same time using the ship ' s weapons to defeat an attacking alien vessel similar to their own . Upon defeating the ship , the abductees celebrate and Sally or Elliott ( whichever gets to the player first ) reports that in the midst of all of the chaos on the bridge , Elliott and / or Sally pushed a button which dropped a beacon on the surface near the Recon Craft " Theta " crash site . This beacon allows the Lone Wanderer to return to the Capital Wasteland or teleport from there to the Mothership ( though most of the ship is now inaccessible ) . Notes . The world map location appears to be either the Ranger Compound or the player character ' s last known fast - travel location while on " Mothership Zeta " .