There is also River Cartwright. He is a young agent trying to find his place among the misfits in the slow horses. Another important character is Diana Taverner. She is involved in the power dynamics within the intelligence agency. These characters interact in complex ways, with their own goals and secrets that drive the plot forward in the 'slow horses novel'.
In the 'slow horses novel', apart from Jackson Lamb, River Cartwright and Diana Taverner, there are other characters as well. There are agents who are disillusioned with their positions in the slow horses department. Each character has their own backstory that contributes to the overall atmosphere of the story. For example, some characters have past failures that led them to be in the slow horses, and they are either trying to redeem themselves or are just trying to get by. Their relationships are full of tension, whether it's between superiors and subordinates like Lamb and Cartwright, or among colleagues vying for power and recognition like Taverner and others.