Clark Kent called in Emil when he found out that Tess's assistant Eva Greer had impersonated Chloe Sullivan and Emil explained that Eva was a shapeshifter. He warned Clark that Chloe could be caught in the crossfire, and that Tess may kill the other members of her team as she did with Eva with just one push of a button. Clark asked Emil to isolate the GPS signal in their brains so that they could track Tess' team. Clark and Emil tried to call Tess and warn her that a member of her team, Parasite, had stolen Clark's powers and set out for revenge. When their attempts were unsuccessful, Emil lent Clark a car to get to Smallville in order to warn Tess in person.
Chloe called in Emil after Tess held Lois Lane at Belle Reve after she went into a coma and Clark stopped Tess and as a result was locked into Lois's memories. Chloe stoped Emil from removing Clark from Lois's brainwaves, once she told him of the reports Tess had on Lois that stated that the more times she went to see her therapist, the more memories of the future she saw she recovered.
Both Tess and Emil were present at Clark and Lois's engagement party at Watchtower. Later, Tess, Emil, and Lois were all brought into questioning by the VRA for their involvement with the heroes. Lois tried to text Clark but Tess and Emil silently informed her that their phones had been bugged. Lieutenant Trotter interrogated Emil, Lois, and Tess separately at the Daily Planet but none of them give her the answers she was looking for. Lois managed to escape while Emil and Tess were sent to a warehouse, presumably to be executed. At the warehouse, Clark arrived and saved Tess and Emil by defeating Trotter and her men in a brief battle. He asked them where Lois was but their silence made him realize they had no idea and that she was still missing.
Emil and Tess attended Clark and Lois's party at the Kent farm where they drank from an enchanted bottle of champagne which caused them to become amazingly drunk and wild. The two of them somehow ended up signing karaoke at the Ace of Clubs with Emil dressed as an Elvis impersonator.
At the end of the next day after the effects of the magical champagne ended, Tess met Emil at the Watchtower and she joked about him. They begun to forge an emotional bond with each other until they were interrupted by Lois and the others who found the camera that Emil had recorded the wild night, the video revealed that Tess and Emil had made love in her office at the Daily Planet, much to both their embarrassments.
Clark Kent had been sent to the Earth-2 universe that Clark Luthor had came from and Tess was working on a way to distract Luthor while Emil and Lois worked on repairing the destroyed mirror box in order to bring Kent back. Later Tess and Emil were talking about Gold kryptonite, and how it had the ability to permanently take away Clark’s powers. Tess told him that she would get her team on it. Emil then inquired about Tess’ dinner with Ultraman. He told her he reviewed the footage of them together, and that she looked tempted to take him up on his offer. Tess told Emil that he didn't know the kind of person she really was. Emil said he did know the real her, even if she didn't believe it yet herself.
Six months after her death, Tess reemerged in the form of a 2nd conscience within her half-brother Lex Luthor. When Lex managed to intimidate Emil into letting his men take over Hank Henshaw's life-threatening operation, Tess appeared again and asked how could Emil give in to Lex's demands. Lex admitted that it took a bit of arm-twisting and manipulation for him to do so. Lex then asked if Tess knew Emil "in more than one way", a reference to their sexual relationship. An offended Tess slapped Lex and told him to go to hell, implying she still very much cared for Emil.
At Watchtower, Clark, Lois and Oliver stand patiently as Emil downloads a grateful Tess into a computer system making her a hologram.
Emil arrives at Watchtower, where he updates the software and "wakes up" the consciousness of Tess Mercer. He tells her he could make a uniform especially for her so she can put some clothes on her holographic representation. Tess doesn't seem to be interested in that idea because as she says clothes are for people and at the moment she is not an actual person. They also talk about whether she dreams when she is in stand-by but their conversation is interrupted by an assault at Seattle, involving men with robotic suits.
Days later Lex Luthor orders an attack at S.T.A.R. Labs, sending his men to invade the facility. Emil decides to stay and confront the invaders. One of them shoots Emil with his gun leaving Tess, who is also inside the facility and all that time was watching from a screen, horrified. Tess decides to take action and do whatever she can to save Emil's life. She then tries to call 911 but she fails because as she is informed local communications are jammed by LexCorp. So she takes the control of a huge robot inside the facility and is heading towards the wounded Emil saying to him to hold on.
Later when Emil leaves hospital, after being shot, he visits Tess and they talk about what happened earlier. She says she did not kill Lex because she dreams, and if she has dreams, it must means something. Not knowing why, she feels that if she is getting a second chance, she does not want any blood on her hands or darkness in her heart. Tess also tells Emil that she reconsidered his idea of making a uniform, clothing her holographic design.
- With Tess's death, Emil has lost two women he has had a romantic interest in, the first being his wife.
- Tess: Hey, hound dog. You really rocked this town.
- Emil: I suppose that's supposed to be humorous?
- Tess: It's just... well, it was a nice surprise to see our mild-mannered doctor have a special power of his own.
- Season Ten, Fortune
|Tess Mercer in Smallville|