Jack question Owen about Gwen and Rhys , and he state that Rhys ' mother Brenda ( Nerys Hughes ) is with them . Tosh mention that she saw Brenda with Gwen 's mother Mary in the garden . Tosh and Jack rush to the couple 's room , where Jack identify Brenda as an alien and call her an " ugly bitch " . After Brenda protest her innocence and Rhys punch Jack , Gwen state that Rhys ' mother is not the shapeshifter as Brenda wear a distinctive perfume . Torchwood reach the garden to find the Nostrovite , in Brenda 's image , with Mary . The alien hold Mary hostage , demanding that Gwen give her her child . Gwen walk towards them and as the Nostrovite release Mary , Gwen reveal a hidden gun in her wedding bouquet and fires at the creature . Owen suggest using a piece of alien equipment called the singularity scalpel to destroy the alien fetus . He send Gwen to her room and teach Rhys how to use the scalpel ; Owen cannot use it himself due to injuries sustained in his undead state . Gwen is approached by Jack and reveal to him that she would have married Rhys a long time ago if she had not met him . She lean in as he appear to be ready to kiss her but he reveal himself to be the Nostrovite . Owen enters , shooting the creature whilst Gwen exits with Rhys . The Nostrovite , still in Jack 's form , attempt to attack Owen only to be repelled by the fact he is dead .