Dirty Business

Two amateur detectives in an Oxfordshire village discover dying fish in their river. When they contact the water company for answers, the company's odd, evasive response prompts them to launch an investigation that continues today.

• Cast: David Thewlis, Jason Watkins, Posy Sterling, Tom McKay, Alex Jennings, Asim Chaudhry, Alice Lowe, Chanel Cresswell