- "In every relationship, one person stands while the other one kneels. I will not be forced down again." - Tess Mercer
- "I wouldn't want you to be." - Major Zod
Tess was held captive by Zod following his release from the Orb. He was extremely violent with her and Tess seemed to have resigned herself to being his hostage. She was confused by the fact that the voice she had previously heard from the Orb was not Zod's voice and was intrigued to how he had come to be on Earth.
It was revealed that Tess was actually double-crossing Zod, as she was merely playing the part of a defenseless woman so as not to arouse his suspicion. However, she was actually trying to establish what the Kryptonians were doing on Earth by infiltrating their inner circle.
Tess became concerned when she discovered Zod's lab where he had transformed John Corben into a cyborg, as she theorized that the Kryptonians were closer to obtaining their powers. She met Zod again when he gatecrashed her launch of the Metropolis solar tower. Tess was surprised and nervous to see him. After the meeting was over, Zod told Tess that he had been working to make LuthorCorp the most advanced company on Earth. In return, he wanted her to reveal the identity of the one who betrayed them: the Blur. He explained they got a sample of the Blur's blood after spreading the zombie plague, but Tess arranged for the samples to be destroyed. Zod was suspicious of Tess and believed that she wanted to use the Blur as a bargaining chip. Tess admitted that she wanted to be equal partners with Zod and was desperate for him to respect her but he claimed that could never happen as Kandorians were superior to humans.
With no concern for Tess' life, Zod arranged for one of his soldiers to go undercover as one of Tess' security guards to force Tess to tell him what she knew by threatening to kill her. To Zod's surprise, Tess was able to kill the security guard, showing Zod that she was more powerful than he had originally realized. This made Zod rely on Tess' help to find Jor-El when he came to believe that he was the Blur.
Zod began to flirt with Tess but she told him that she wasn't interested in a romance with him but agreed to help him. However, when she found Jor-El's clone she didn't tell Zod. Nevertheless, Zod quickly discovered her deception and Tess appeared angry, although once he left Tess smiled indicating that she was double crossing him again.
Later Zod watched Tess take a bath and entered alarming Tess but Zod calmed her down. Tess asked if he wanted join her but Zod stated that she was already in bed with Kal-El and that his towers were nearly complete. Tess stated she thought he needed the Book of Rao his towers but Zod stated him and his people found another to complete them. Zod went on to say that Tess's satellites were behind schedule and Tess said only she can really. Zod quickly picked her wine glass and stated he doesn't need her. Tess warned him he was digging his own grave and Zod stated to make room for both of them. Tess went on to say that Zod's people were looking to Clark as a new leader, stating that he is the promise for their future where as Zod was tainted. Zod caught on to what Tess was planning to get rid of him. Just before leaving he threatened Tess stating that when his towers come online that she will need mercy. Zod later sent a gemstone kryptonite infected Clark Kent after her since he had told her she was Jor-El's killer.When Tess discovered that Zod had his powers restored, she wanted to make sure and confronted at the Kent Farm. Tess shot a bullet at Zod and he was able to hold it in his hand without any harm coming to him. Once Zod revealed his powers to her, he was prepared to kill her until she pulled out a piece of kryptonite from the gun and started to weaken him. Zod collapsed to the ground and then Tess put the kryptonite away, then began to kiss him, with him kissing her back. They slept together at the Luthor Mansion with Zod commenting Tess and asking how she weakened him back on the ground. She refused to answer and then kissed him before getting dressed and out of bed. Zod later phoned Lois Lane posing as the Blur and asked her to get information on Tess to which Lois agreed.
Their relationship turned sour when Tess overtly tried to stop Zod. She confronted him at the Fortress and tried to weaken him again with kryptonite "brass knuckles", but Zod recovered and badly burnt her face, which put her in hospital in a critical condition. She was later pronounced dead. This was the last time Tess and Zod ever meet.
In a possible future, Tess allied with Zod and the Kandorians and turned the Luthor Mansion into the main headquarters of General Zod. Tess proclaimed to Lois Lane, who returned after being "missing," that she was the planet's savior because she'd helped make the planet better than how it was before but Lois only accused her of treason. Tess told Zod that she had tried to convince Clark Kent that they are doing good for the world but that he wouldn't come around. She was initiated as a Kryptonian soldier and citizen by Zod before Lois's eyes and was given dogtags. During an attack on the Mansion by a resistance led by Chloe Sullivan and Oliver Queen, Tess was killed and Zod escaped.
- Zod: I find the pleasure I get from wine much more satisfying. Every sip... reveals a new riddle... a new truth. Just like you, Tess. Every time we're together, I discover something new. And I can't wait to see what my next sip reveals."
- Tess: The bitter truth. That I'm not interested.
- Season Nine: Kandor
- The partnership between Zod and Tess is similar to Zod's partnership with Lex Luthor in Superman II, albeit with some sexual tension thrown in.
|Tess Mercer in Smallville|
| Zod in Smallville|