Wire in the Blood S04E01 - Time to Murder and Create

Tony is forced to face up to his past demons once more when evidence that he submitted against a murder suspect is torn apart by his legal team. Tony's world is rocked once more when he discovers that Carol has been replaced by a new, combative and wily detective, Alex Fielding. Although the pair take an initial disliking to one another, they soon realise they need to work together to solve a complex murder case.