- Writers: Kenneth Johnson, Scott Peters
- Stars: Elizabeth Mitchell, Morris Chestnut, Joel Gretsch, Logan Huffman
Anna believes she has found a way to identify fifth columnists: they are acquiring human emotions and can be screened for them. They start by checking everyone on board the mother ship. The Visitors announce that humans will be allowed to live aboard one of their 29 ships. Kyle Hobbes convinces Erica, Ryan and the others that they have to let Anna know they're there and that they are a threat. Ryan is increasingly concerned about Valerie's pregnancy which is advancing at a rapid pace. He has to decide whether to tell her what is going on but in the short term has to go on board the mother ship to get medicine or Valerie will not survive the pregnancy.