We briefly meet Tom Turvey in Career of Evil when we learn that he is dating Matthew’s old university friend, Sarah Shadlock. Robin finds him “boring and obtuse.” ¹

In Lethal White, it is revealed that Tom and Sarah have recently become engaged and that Tom has helped get Matthew a new better-paying job at his firm.² Matthew and Sarah often team up and tease Tom about his baldness, a fact that Matthew knows Tom is self-conscious of.³ In most of the instances that we meet Tom, he appears drunk, including at Robin and Matthew’s wedding reception⁴, their housewarming party⁵, and on a night out with Robin and Matthew where Tom appears to have finally lost his patience with Matthew’s teasing.⁶ 

In Troubled Blood, just before Christmas, Robin receives a very angry phone call from Tom Turvey after he has finally learned of Matthew and Sarah’s affair.

“‘Thanks,’ said Tom. ‘Thanks a fucking bunch, Robin!’” ⁷

^{1: Career of Evil, Chapter 2
2, 3: Lethal White, Chapter 7
4: Lethal White, Chapter, Prologue
5: Lethal White, Chapter 7
6: Lethal White, Chapter 40
7: Troubled Blood, Chapter 23}