Nixon and Turner's quest to discover the identity of the serial arsonist takes an interesting turn when they discover that Jay Henderson's ex-girlfriend, Cheryl Wilkes, who claims to be pregnant with his baby, has links to all three of the locations where fires took place – the first being her childhood home, and the second being a foster home where she was placed while she was in care. Elsewhere, Smith and Walker investigate after a seemingly minor spat between a market trader and a customer leads to an assault on the customer's heavily pregnant wife, but would the market trader go so far to attack her in retaliation? Smithy asks Walker if she wants to move in after struggling to find a place to live, while Nixon tells Turner and Hunter she'll be the new DI.