TRUE-CRIME DRAMA Deceit, All 4

THE murder of Rachel Nickell in 1992 has been extensively covered in true-crime documentaries, but this four-part drama takes a close look at one key part of a long and exhausting investigation. Niamh Algar plays a police officer who goes undercover to gather intelligence on the prime suspect, Colin Stagg. Even if you know the outcome, this is still a fascinating look at the process of undercover work and the toll it takes, with a superb performance from Algar.