Tora Ziyal was the illegitimate daughter of Gul Dukat in Star Trek: Deep Space Nine. She was concieved during the Cardassian Occupation of Bajor and was born to Tora Naprem, a Bajoran woman who apparently loved Dukat.
Ziyal has been portrayed by three different actresses throughout DS9's run. She was first portrayed by Cyia Batten in the fourth season episodes "Indiscretion" and "Return to Grace". She was then portrayed by Tracey Middendorf in "For the Cause". Finally, she was portrayed by Melanie Smith throughout all of her appearances in Seasons Five and Six.
Considering the great animosity between the Cardassians and the Bajorans they had subjugated, it would have been considered politically incorrect for Dukat to have any Bajoran family, and so Ziyal spent much of her early life on Terok Nor, out of sight from both the Bajoran slaves and the Cardassian soldiers. Towards the end of the Occupation, she and her mother were sent away to the neutral planet of Lessepia since neither of them would be welcome on Cardassia or Bajor. However, the transport carrying them was attacked by Breen warships and downed on the planet Dovaria where the Breen had established a dilithium mining operation. Naprem had died in the crash but Ziyal survived, and she was taken prisoner by the Breen and put to work.
In the episode "Indescretion", Ziyal was rescued by her father and Major Kira Nerys of the Bajoran Militia. Dukat had originally planned to kill her since the fact that he had sired a half-Bajoran daughter would threaten his political position and his relationship with his wife and seven children back on Cardassia. Kira was able to convince Dukat to spare her and they managed to liberate her from the Breen camp along with thirty Bajorans.
For a time, Ziyal stayed on Cardassia with her father, but as feared, Dukat was demoted and he was disowned by his family when his relationship with Tora Naprem was brought to light. Reduced to towing freight, Dukat took Ziyal with him wherever he went. However, after the Groumall was destroyed and Dukat took command of a captured Klingon Bird-of-Prey, Ziyal returned with Major Kira to live on Deep Space 9. Dukat had conceded that it would be a better life for her on the station than accompanying him on his war against the Klingons.
Life on Deep Space 9
Aboard the station, Ziyal became drawn to Elim Garak, who was the only other Cardassian on the station. Garak was initially concerned that Ziyal might try to kill him, due to the enmity between him and Dukat, though the two eventually developed a relationship. Dukat was outraged when he learned of this development in 2373 upon his return visit to Deep Space 9. At that time, Dukat had been secretly negotiating the alliance between the Cardassian Union and the Dominion. Knowing that he would soon rule over Cardassia itself, Dukat attempted to take Ziyal back with him, promising that "things will change" this time around. Ziyal refused, since Garak was lost in the Gamma Quadrant and she had promised she would wait for his return. In response, Dukat disowned her and would soon condemn her to death with a plan to destroy the Bajoran sun.
The Dominion War
As the war between the Dominion and the Federation began, Ziyal was briefly relocated to Bajor when Deep Space 9 was seized by the Dominion. Three months later, she returned to the station and seemed to have re-established her relationship with her father. Dukat often doted on her, though there was still a strain between them since Dukat was heading the Dominion's war effort against the Federation, whom Ziyal sympathised with. She wanted to believe that her father was not the tyrant that the Bajorans saw him as, but she became disillusioned when Dukat refused to pardon the Ferengi Rom after he had been sentenced to death.
As the battle between the Federation and Dominion forces raged, Ziyal aided Quark in freeing Major Kira from prison. When the Federation forces closed in on Terok Nor, the Dominion began evacuating. Gul Dukat frantically searched the station to find Ziyal and the two found one another in a corridor, and Ziyal admitted that she couldn't bring herself to hate her father. Dukat urged Ziyal to come with him to Cardassia, but she refused and told him that she had helped Major Kira escape. She told Dukat that Deep Space 9 was the only place she belonged and she bid a tearful farewell to him.
As she was about to walk away, Ziyal was shot by Dukat's aide Damar, who declared her a traitor. As Ziyal lay dying on the deck, Dukat knelt over her, assuring her that everything would be alright. Damar tried to pull Dukat away but was shunned, and Dukat wept as Ziyal slipped away.
Following Ziyal's death as well as having victory suddenly snatched away from him at the last moment, Dukat was driven insane.