Bought out by Lumic
Unlike Rose's deceased father, the Pete Tyler of a parallel world was a wealthy businessman. He was head of Vitex, a firm that made soft drinks and a subsidiary of Cybus Industries, which was run by John Lumic.
He was married to Jackie Tyler. They had no children, but did have a dog they called Rose. Shortly before Jackie's fortieth birthday, Pete and Jackie got divorced but kept it quiet as it was bad for business. He threw a party for her, but she was annoyed with him as he had put that she was forty on the banner, not thirty-nine, which she wanted it to say. That day, Pete had attended a meeting aboard John Lumic's Zeppelin.
In this meeting Lumic told Pete and the others of his plans to change humans into Cybermen. The President prohibited it. Pete tried to make Lumic feel better, telling him Great Britain was not the only country in the world. (TV: Rise of the Cybermen)
Fighting the Cybermen
During Jackie's party, Pete met "his" daughter, Rose, whom he began to see a resemblance towards him and Jackie. Later on, Cybermen broke into the house and started killing the guests. Pete escaped with the Tenth Doctor, Rose and the Preachers. They were surrounded by the Cybermen, who threatened to delete them, as they were "incompatible for upgrading". (TV: Rise of the Cybermen) Before they were deleted, the Doctor used an Artron power cell to defeat the Cybermen, and they fled in the Preachers' van driven by Mrs Moore.
As they drove away, Pete revealed he had been secretly feeding information to the Preachers, under the code name "Gemini". He took part in the plan to stop the project, disguising himself using dead EarPods. He and Rose entered the Cyber Factory and waited to be "upgraded". The plan failed. A Cyberman approached after overhearing their conversation and revealed itself to have been Jackie, which exposed Pete's emotions by causing him shock and horror.
Pete was taken with Rose to the Cybermen's control centre and watched as the Doctor spoke with the Cyber Controller that had once been John Lumic. The Doctor defeated the Cybermen by making them feel emotion by inputting the code which broke the emotion inhibitor. As the factory started to burn, Pete and the others escaped to the roof. Jake Simmonds and Mickey Smith lowered a ladder from the Zeppelin they were flying so the others could climb up. The Cyber Controller grabbed onto the ladder as well, but was sent tumbling into the exploding factory after Pete used the sonic screwdriver to break the ladder under him.
He found out Rose was actually the daughter of his parallel self from the Doctor's universe. Because he and his Jackie had not had a daughter, he simply walked away stunned, under the pretence of helping the Preachers. Rose and the Doctor then departed in the TARDIS. (TV: The Age of Steel)
Saving the Earth
After saving his world from the Cybermen, Pete joined Torchwood along with Mickey and Jake. They developed technology to permit travel between parallel universes.
During the Battle of Canary Wharf, the Doctor was brought back to the parallel universe via the dimensional transporters that Pete's Torchwood had developed. Pete asked him to help save his world, where the Void opening was causing a rise in temperature.
Pete travelled to the battle, where he saved Rose's Jackie Tyler from two Cybermen, killing them with a Preacher gun. Pete then tried to draw the line between him and Jackie, explaining to her that he was not the same Pete she had married and vice versa; but he ultimately gave in to his emotions and he and Jackie embraced.
Once the group made their way to the Void Room of Torchwood Tower, the Doctor decided to name the parallel world "Pete's World". After the Doctor explained his plan to open up the Void from one side, Pete teleported Jackie, Rose and himself to the parallel world. However, Rose teleported back to be with the Doctor. The Doctor and Rose opened the Void, which started to suck all the Cybermen and Daleks in. As the Void was in full force, Rose let go of her hold and flew towards the Void opening as well. Before Rose fell into the Void, Pete teleported back and caught her, saving her life but trapping her in his universe forever.
A few months later, Pete drove his new family to Norway after Rose had a dream in which the Doctor called her there. By this time, Pete and Jackie had already started a relationship and Jackie was pregnant. Also, Rose had begun to call him "Dad". (TV: Doomsday) Pete and Jackie had a son, whom they named Tony. (TV: Journey's End)
Exploring parallel universes
After Torchwood developed the dimension cannon, Pete announced that it had started working due to barriers between worlds appearing to be thinner. He tried to dissuade Rose from being the first volunteer to test it but she insisted. He took the role of “Control” and communicated with Rose via her phone, checking in with her as she explored a parallel universe. When she asked to save multiple people, including his and Jackie’s counterparts, from dying after their Earth’s Sun was extinguished, Pete refused as the cannon had only been designed for one. He continued to reject her request, even when his counterpart stole Rose’s travel disc. After reclaiming it, Rose contacted Pete to arrange her return and he was furious when she risked herself by bringing Clive Finch back with her. (AUDIO: The Endless Night)
Pete was tasked with taking care of Tony while Rose, Jackie and Mickey travelled back to their Earth to stop the Daleks. After being returned to "Pete's World" by the Tenth Doctor, Jackie commented that Pete would have to come and get them from Bad Wolf Bay in Norway, where they had been dropped off. (TV: Journey's End)
After President Harriet Jones formed UNIT by combining the Preachers and Torchwood, Pete and Rose joined up whilst the Meta-Crisis Tenth Doctor acted as scientific advisor and Jackie was the dinner lady. After the Doctor and Jackie fell out, (AUDIO: The Siege of Big Ben) Pete and Rose conspired to put them on the same zeppelin flight to Hull to work through their differences. (AUDIO: Flight Into Hull!) Peter also became a grandfather, as Rose and the Doctor had a child, Mia, together. (COMIC: Empire of the Wolf)
He was once just a normal guy with ideas for how to get rich, often referred to as "daft, little schemes". (TV: Rise of the Cybermen, Doomsday) By the time of the Doctor's visit to their world, things with Pete and Jackie had fallen through, although the two kept this quiet as he felt it would be bad for business to do otherwise. (TV: Rise of the Cybermen)
Although on the surface Pete enjoyed a good working relationship with John Lumic, he was secretly worried about the direction Lumic was heading in and worked as an informant for the Preachers (although at the time he thought he was broadcasting to the security services). Upon meeting them in person following the Cybermen's attack on his mansion, he likened them to "Scooby-Doo and his gang" and was not impressed when Ricky admitted he was London's most wanted for parking tickets, leaving Pete wondering what he had become involved in. (TV: The Age of Steel)
While Pete could be protective of those closest to him and his world, he was, to an extent, indifferent about anything else; when the Doctor told him sealing the gap between their worlds would mean several million Cybermen would be stuck on the Doctor's side, Pete merely said it wasn't his problem and he was only concerned about what happened to his world. He did, however, have some respect for the Doctor, believing that if anyone could defeat the Cybermen and Daleks and seal the gap between their worlds, he could. Despite initially acting disattached, he ultimately risked one last jump between worlds to save Rose from the Void. (TV: Doomsday)