Matthew worked as Yvonne Hartman's secretary at Torchwood One, although he considered himself to be little more than a personal assistant. He was, at some point, recruited by Pascal Babich, CEO of Blind Summit, and entered into a romantic relationship with him.
Matthew supplied Blind Summit with Excellium and the means of making Arachmeds. He was a successful Excellium subject. Yvonne suspected that there was a mole in Torchwood who had supplied Blind Summit with the Excellium and spiked Matthew with a truth serum to determine if he was trustworthy. The Excellium had made him immune and he was thus able to lie. In truth, he was planning on becoming director of Torchwood.
He saved Yvone and Ianto Jones from Pascal's soldier at a coffee shop, mended Ianto with the Arachmed and dropped the two off at 56 Stanmore Crescent. Yvonne told Matthew to keep her continued presence in London a secret, as Torchwood believed that she was on a wine tour in France.
Matthew and Yvonne elicited Ianto's help to infiltrate Blind Summit. Matthew lent him one of his favourite suits, although he was worried that Ianto would ruin the shape. He revealed his true colours after Ianto and Yvonne were detained by Pascal. Pascal was decapitated by Tommy Pierce and Matthew left by Yvonne to be killed by the Arachmed. (AUDIO: Blind Summit)