The Walls of Jericho
S01E03 - Airdate: 1988-10-10
Runtime: 45 min
It's been six weeks without any further activity from the aliens since the destruction of their warships. The powers-that-be believe that the Blackwood Project has done its job and prepare to shut it down. In reality, the aliens are very much alive, but have put all efforts in combating the radiation that protects them from the bacteria from killing them as well.
Episode details and rating from TVmaze.