When the Starbug crew were flying through a Psiren Infested asteroid belt, they received a transmission from one of the other ships in the same situation. The distress call came from a woman who identified her self as Captain Tau of the SCS Pioneer. She was shown battling the Psirens over the viewscreen, but was shot dead only for her weapon to be picked up by Kristine Kochanski. Both were revealed to be illusions created by the Psirens.
- Captain Tau is named after Red Dwarf's captain in the American pilot episode of Red Dwarf (1992). Both characters died after speaking only a few lines.
- Although Kochanski was obviously an illusion, it is possible that Tau was a real person killed by a Psiren.
- During commentary for this episode, the cast bemoaned that Anita Dobson's character was given a much cooler weapon than they ever got.
- When the producers approached Brian May about doubling for Lister's guitar work in Psirens, they decided to also ask May's partner Anita Dobson if she would consider a small role. When she said yes, they were sorry that they did not have a more substantial part for her.