Later at the Pitt-Rivers Museum in Will's world, he again met Lyra, who was acting under the false name Lizzie and did not recognise him. He spoke to her about the trepanned skulls and gave her a card, telling her that she could contact him if she wanted to know more.
The next day, when Lyra was being chased by the men who were looking for Elaine Parry's writing case, Boreal offered her a lift in his Rolls-Royce. He took her to Summertown and deftly stole her alethiometer without her noticing. Once she realised, Lyra and Will went to Boreal's house to ask for it back. Boreal told them he would return it in exchange for the subtle knife.
That evening, Boreal invited Marisa Coulter to his house. They drank Tokay and discussed the different worlds, Lord Asriel's plans and Lyra. Will stole the alethiometer while Lyra provided a distraction and both managed to escape. Both Boreal and Coulter were unaware of who stole the alethiometer.
The next day, Boreal visited the Dark Matter Research Unit under his pseudonym of Charles Latrom. He offered to fund the research of Oliver Payne and Mary Malone if they would be willing to focus their research on the manipulation of consciousness. Although Malone was reluctant to work with Latrom, Payne called him immediately after she left the laboratory.
Some time later, in the world of Cittàgazze, Boreal was seduced by Marisa Coulter into telling her everything he knew about the subtle knife. Coulter poisoned his glass of wine and Boreal died as a result.
In Will's world, Boreal had a servant named Allan who acted as a doorman and a chauffeur. Boreal spoke openly about the subtle knife and the World of Cittàgazze in front of Allan, suggesting that the master trusted his servant greatly.