This fourth series of four episodes sees the formula being tweaked slightly and successfully. The elements that have made the series (along with the original Morse) work are maintained with fine production values, strong guest roles going to a wide range of good actors, and convoluted murder mysteries that nobody can figure out.
This time the relationship between Lewis and side-kick Hathaway is allowed to develop. Previously Hathaway had been portrayed as being somewhat enigmatic. With Lewis being unable to work him out this led to friction between them. After working together for four years they now accept each other and this lets them engage in plenty of entertaining discussions along with some nicely played gentle comedy. This series also sees development in the relationship between Lewis and Doctor Hobson. She has been around since the last few episodes of Morse and so their friendship and the possibility of them becoming attached is logical. The series manages to avoid becoming too soap-like with the will they/won't they question and their attempts to get closer doesn't get in the way of the murder mysteries. Sadly, this concentration on Lewis's relationship with the two main leads means that his boss Innocent has less to do this year.
The other noticeable change is a drifting away from the murderous Oxford dons style of story. All the stories are still set in Oxford, dons feature heavily, and much of the footage is shot within college, but there's more of an Agatha Christie's murder at the mansion feel. So two stories take place over short periods of time in enclosed environments with a cast of dodgy characters who all have their own red herrings. Dead of Winter features a murder at a stately home that happens to be the place where Hathaway grew up. This helps to fill in more of the background on Hathaway's past in a believable way. The more comically orientated Your Sudden Death Question revolves around a murder at a quiz weekend and features great turns from Timothy West and Alan Davies, amongst others. Both of these episodes are a lot of fun.
A more traditional story is Dark Matter in which an astronomer is killed and which features Robert Hardy and Warren Clarke's odd accent. The stand-out story of the series is the final one Falling Darkness in which Hobson appears to be implicated in a series of deaths. This episode is a perfect mix of strong emotion, complex mystery and good character interaction. I hope this series runs for a while longer.