Fey Truscott - Sade Fey Truscott - Sade was an undercover agent for the British government , later a companion of the Eighth Doctor . She merged with Shayde into a being known as Feyde . Biography . Fey first encountered the Eighth Doctor in an adventure involving psychic weasel s in Russell Square . On that occasion the Doctor gave her a Stattenheim Summoner - a device , disguised as a tin whistle , that could contact the Doctor ' s TARDIS . ( COMIC : " Tooth and Claw " ) In 1937 , the Threshold kidnapped Fey and put a mind control device in her head to spy on the Doctor . ( COMIC : " Wormwood " ) In 1939 , Fey called on the Doctor and his companion Izzy to help her investigate the sinister Varney . ( COMIC : " Tooth and Claw " ) The defeat of Varney proved costly for the Doctor . He had injected himself with a deadly bacillus and was dying . ( COMIC : " Tooth and Claw " ) Now secretly under the control of the the Threshold ( COMIC : " Wormwood " ) , Fey piloted the TARDIS to Gallifrey , where the Doctor ' s body was cured and his mind placed into the Matrix to heal . ( COMIC : " The Final Chapter " ) In the Matrix , an attempt was made on the Doctor ' s life by a secret Time Lord sect called the Elysian s . The plot was foiled by Shayde , an artificial being created on Gallifrey . The assassination attempt was part of a plot by Overseer Luther . The Doctor thwarted Luther by short - circuiting his watchtower ( a gigantic TARDIS ) , but apparently at the cost of his eighth body . As Izzy and Fey watched , the Doctor regenerated into a new incarnation . ( COMIC : " The Final Chapter " ) However , this was a ruse . The Doctor had realised Fey was under external control when she had piloted the TARDIS even though the TARDIS manual was in Gallifreyan script , which she couldn ' t have understood . Just before the Doctor prepared to sacrifice himself , Shayde offered to take his place and fake a regeneration . This would allow them to bring a newly regenerated and weaker Doctor to them . Both disguised with personal chameleon circuit s , Shayde would hold their attention while the Doctor sabotaged the Threshold ' s operations . In Wormwood , a Wild West town on an alien moon run by the Threshold , the Doctor ' s plans came to fruition . The Threshold removed their implant from Fey , gloating she had been an unwitting spy for them . Preparing for the final confrontation , Shayde and the Doctor revealed themselves to the Threshold . However , Shayde had to contend with the Pariah , an immensely powerful prototype version of himself . Shayde could not defeat the Pariah on his own and she crushed his skull . Comforting the dying Shayde , Fey merged with him and together they killed the Pariah and eliminated the Threshold . The shared being was dubbed Feyde by the Doctor , although each of them retained consciousness . Feyde decided to leave and deal with what had just happened to them . ( COMIC : " Wormwood " ) Fey returned to 1939 , where she continued to work for the British government . Fey spent two years fighting the Nazi s with Shayde , though she felt some frustration because Shayde would not allow her to use their powers to kill Adolf Hitler , as this would have changed history . Over the course of their union , Fey and Shayde began to develop a close love / hate relationship , sharing secrets , but often vigourously disputing the use of their power to influence history . Fey resented Shayde ' s unwavering loyalty to Rassilon and his lack of individuality . These traits implied she was in love with Shayde , but could not admit this to herself or her partner . ( COMIC : " Me and My Shadow " ) In 1941 , she received a sub - ether summons from the Doctor — Izzy had been kidnapped and the Doctor needed Shayde ' s abilities to track her on the planet Oblivion . They recovered Izzy . After Izzy was restored to her own body after having exchanged it with Destrii ' s , Fey encouraged her ( Izzy ) to embrace her true sexuality and gave her a passionate kiss . Feyde returned to World War II . ( COMIC : " Oblivion " ) At some point , the Doctor believed Fey to have died . The Twelfth Doctor was therefore surprised to see her after he had defeated the Phantom Piper . Fey warned him that the Absence was coming , and that he should assemble his forces . ( COMIC : " The Phantom Piper " ) Powers . As a merged entity , Fey was able to use Shayde ' s powers , including the ability to travel through time and space unaided , phase through solid objects and fire self - generated " psychic bullet s " . ( COMIC : " Me and My Shadow " , " Oblivion " )