The Darkening Eye ( audio story ) The Darkening Eye was the sixth story in the third series of " The Companion Chronicles " . It broke the unwritten rules of " The Companion Chronicles " by featuring Nyssa relating an adventure with the Fifth Doctor . Typically , the range dealt with incarnations of the Doctor whose actors were not able or willing to participate in monthly " Doctor Who " releases . Nyssa was the Fifth Doctor ' s most constant audio companion , so her inclusion in this range was unusual at the time . However , Turlough , Peri Brown , Evelyn Smythe , Ace , Bernice Summerfield and Charlotte Pollard each later appeared in at least one " Companion Chronicle " . Publisher ' s summary . While investigating a debris - littered battlefield in deep space , the TARDIS crew are salvaged by an ancient race of collectors known as Dar Trader s . Separated from the Doctor after an accident , Adric , Tegan and Nyssa find themselves at the mercy of the Traders ' curiosity . But the Traders have salvaged a cabinet from the battle that could be very dangerous indeed . What does the suave assassin , Damasin Hyde , know of the cabinet ? And why is everybody so interested in the missing Time Lord ? To find the Doctor , the TARDIS crew will have to enter a violent inter - planetary war . Where someone will die , and it will change everything . Plot . Having detected a dimensional anomaly , the Doctor materialises the TARDIS on a rapidly deteriorating ship . Although there is seemingly no atmosphere , he and his companions are nevertheless able to breathe . Shortly after their arrival , Nyssa sees a figure moving in her peripheral vision , which she soon discovers is a Dar Trader . She describes them as producing a smell similar to ammonia . The Doctor has never previously heard of the Dar Traders . One of them claims that the four of them have " shifting death signatures . The Dar Traders , who not only trade but consume the dead , have no jurisdiction over the living . After the structure of the ship further destabilises , the corridor in which the Doctor , his companions and the Dar Traders are standing splits in two . While Adric , Nyssa , Tegan and one of the Dar Traders remain in the half of the corridor which is still connected to the main body of the ship , the Doctor ends up on the other half , although he has access to the TARDIS . The second Dar Trader is blown out into space . Given the unstable nature of the ship , the surviving Dar Trader suggests that he , Adric , Nyssa and Tegan retreat to his vessel . The walls of the Dar Traders ' vessel are adorned with the carcasses which they have previously collected and salvaged . They are preserved using formaldehyde . Tegan describes the remains as " ghoulish . " The Dar Trader tells them that they collect the carcasses in order to discover the experiences of the deceased at the moment of death . The Dar Trader ' s scanners detect that the TARDIS has materialised on the surface of the planet below , leading Adric to suggest that it is once again malfunctioning . The vessel features dozens of Dar Traders in stasis . They are attempting to discover what , if anything , exists in the threshold between life and death . While in the Dar Traders ' catalogue device , Nyssa experiences a vision of herself being held by Tegan in a field of leaves . The Dar Trader interrupts the cataloguing process and states that , as a Trakenite , death is attracted to Nyssa but she can master and calcify it . He proposes a trade . Nyssa agrees on the condition that he spare Adric and Tegan from the cataloguing process and that they retrieve the Doctor and the TARDIS from the planet . The Dar Trader tell Adric , Nyssa and Tegan that they trade in death as they sought to experience it without actually dying . The pod which the Dar Traders retrieved from the planet is constructed from dwarf star alloy , an extremely dense metal often used to aid in the travel between dimensions . Adric , Nyssa and Tegan determine that this was the source of the dimensional anomaly . In a secret compartment of the pod , Adric , Nyssa and Tegan discover a middle - aged man dressed in a black suit with a red shirt . Although the Dar Trader believes that he is dead , the man opens his green eyes , pulls out a dagger and stabs Adric in the chest . However , he did not die as he is an Alzarian , meaning that his heart was on the right side of his chest rather than the left . Having been restrained by the Dar Trader , the man tells Nyssa that he is an assassin for hire named Damasin Hyde . On the surface of the planet , Damasin discovers that his ship has been raided and all of his equipment has been stolen . His intended target is the Doctor . He has gained possession of his glasses . The Dar Trader claims that he can locate the Doctor by tracking his death signature . Damasin , who claims that killing people is something that he is " exceptionally good at " , tells Nyssa that he cannot die as his cabinet is able to keep him in a perpetual state between life and death , meaning that he is the perfect assassin as he is incapable of being killed . After being stabbed by one of the soldiers who survived the battle , Nyssa is dead for three minutes but she is brought back by the Dar Trader , who conducts a trade with her . She awakens to find herself being cradled by Tegan in a field of leaves , which is consistent with her earlier premonition while in the catalogue device . During Nyssa ' s convalescence , the Dar Trader and Damasin locate the Doctor in a nearby town . They find him on his knees outside the TARDIS being threatened by a several ragged soldiers , who seek to gain possession of the TARDIS key . Damasin kills them . The TARDIS was unable to materialise on the disintegrating ship as it was dragged to the surface of the planet by Damasin ' s vessel . He tells the Doctor that he requires a Time Lord in order to power his cabinet , given its enormous power requirements . Damasin shoots the Doctor but he survives . He determines that the cabinet is the source of the dimensional anomaly and that if Damasin were to activate the cabinet using the Doctor ' s energy , the dwarf star alloy would amplify the effect and create a hole in the universe , destroying the entire planet . By bonding herself with the Doctor ' s energy in the cabinet , Nyssa enters the threshold and turns Damasin to stone .