In 1972, while working at Brixton station, Lloyd was attacked by the animated corpse of a Hakuai called Moan'na. Lloyd fell ill and was taken to King's College Hospital. The bacterial infection, mutated by Moan'na's biological resequencer, transformed Lloyd into a Hakuai. Lloyd then fled, taking Jess with him. The infection went airborne, but the Twelfth Doctor cured Lloyd by feeding Moan'na's resequencer, keyed to Jess and Devina's familial DNA, to Lloyd, curing him. He used the TARDIS' telepathic circuits to rewrite the DNA of the other infected humans to return them to normal, but this caused the TARDIS to overload, trapping the Doctor in 1972. With nowhere for the Doctor to go, Devina offered him to stay with the Collins family. (COMIC: The Pestilent Heart)
After the Doctor moved himself and the TARDIS into the Collins residence, he and Lloyd talked about his infection. While the Doctor was talking about the "beasties" that threatened Earth, he was attacked by Lloyd's cat Tibbsy. Lloyd tried explaining to the Tibbsy that the Doctor was. He told the Doctor that like Lloyd, Tibbsy was always looking out for his family. (COMIC: Moving In)
On Christmas Eve, Maxwell asked Lloyd if he was still getting a bike for Christmas. The following morning, Lloyd opened the front door, where he was met by the entire street, who Devina invited for breakfast as a reminder that they were a community and to remember Carmen, who had died over Christmas 1971. (COMIC: Be Forgot)
In 1973, the Collins family were knocked out by Katya Dabrowski and her men, and taken to an apartment in central London. They were greeted by the Master, who told them the Doctor was a threat to them and a powerful and deceitful alien. Ensuring the Collins family that the Doctor would never hurt them again, the Master used the artron energy in their body as a means of opening a portal to a time locked dimension, which they were also sent to. Jess, Devina and Lloyd were separated from Maxwell. A tentacle in the dimension caused Jess' leg to necrotise, making it harder for her to walk. While trying to escape from alien creatures across a ridge, Jess and Devina saw them age Lloyd to dust.
Maxwell reunited with Jess, and a being called Kiadine, who the Time Lords had imprisoned on this world, reversed what had happened to Lloyd. The Master found Kiadine, and was offered his temporal powers, and the Doctor and the Master fought with each other over the power of the chronon storm, when the Collins family pulled the Doctor back, standing together against the Master. The Master attacked them, and this blast was repelled with the same artron energy in the bodies of the Collins family that had brought the Master to the dimension. The temporal effects on Jess and Maxwell were also reversed. The Master survived this attack and left, and with no-one left to keep time in check, the Doctor and the Collins family evacuated. After Gabriel's funeral, the Doctor said goodbye to the Collins family and left in a fully repaired TARDIS, believing he had outstayed his welcome. (COMIC: Doorway to Hell)