Five years after the death of his long-time police partner and a while later the death of Valerie, his wife, by a hit-and-run driver in London, Lewis returns to Oxford after a couple of years in the Bahamas where he was a detective.

Lewis and the much younger Detective Sergeant James Hathaway investigate the death of an American college student, Regan Peverill. The trail leads to another student, Danny Griffon, a man with a family secret whose previous brush with the law was investigated by a certain Inspector Morse. Cryptic doodlings by Morse on a crossword left in the original case file yield important clues: Morse already knew the truth!

Another family intimate is a talented young horn player vying for a scholarship in a privately endowed competition named Endeavour, another sign of life from Robbie's former partner!

Meanwhile, Lewis new boss, Chief Superintendent Jean Innocent, has plans to move him off the front lines to a training assignment, which he is determined to resist.

This episod also starred Clare Holman, reprising her role as pathologist Laura Hobson; Jemma Redgrave, Lizzie McInnerny, Michael Maloney and Jack Ellis. Morse creator Colin Dexter makes a Hitchcockian appearance as a college scout.

See the PBS preview!

Lewis and Hathaway investigate a murder involving a group called the “Sons of the Twice Born”, named after an epithet of Dionysus relating to his birth, whose activities are shrouded in Greek codes, quotes from Nietzsche and a Dionysian fondness for drugs. The title is part of a quotation from Euripides, the full quotation is “Whom the gods would destroy, they first make mad”.

When an ambitious Oxford student is found dead in her hotel room after inviting a reformed computer hacker to speak at the Union, Lewis and Hathaway are called in to investigate. The pair are soon drawn into a case driven by celebrity, ambition and dangerous sexual politics, which strikes alarming chords with Lewis.

Lewis and Hathaway investigate the apparent suicide of a housewife living in Summertown.

Lewis and Hathaway investigate the death of a maintenance engineer found shot in the head in the basement of the Bodleian Library. A search of the dead man’s house reveals a stash of valuable volumes and a connection to the local gamblers anonymous group, with further probing exposing a scam involving two Oxford academics.

Neil Pearson and Haydn Gwynne guest star with Darren Clarke, Sam Alexander, Emily Beecham, Tom Riley, Ian Burfield, Clare Holman, James Weaver, Felix Scott, Jack Gordon, Jeany Spark, Caleb Rowe and Rebecca Front. University College is featured prominently in this episode, with scenes shot in Radcliffe Quad and at the Shelley Memorial.

Lewis and Hathaway are called in to investigate a boxing scam, a close link to Lewis’ old boss, Inspector Morse, and a love triangle linked to the Stasi. Written By Dusty Hughes. Directed by Bill Anderson.

Lewis investigates when a devout young Christian desecrates a church by committing suicide on its altar, claiming in a call to the police that it was murder. Hathaway recognises him as Will McEwan, an old school friend. As the detectives delve deeper, a series of gruesome murders occur, all involving members of “The Garden”, a modern Christian club, and Hathaway, who once trained for the priesthood, appears to know a lot more than he is willing to tell his boss. Ian McNeice, Matthew Marsh, and Rachael Stirling guest star.

Following the rape of a teenage girl, Lewis and Hathaway stumble across the curious private dinner parties of high school computer technician Oswald Cooper, who ends up being brutally murdered and castrated after entertaining several highly respected societal figures.

A Czech barmaid is found slashed to death by an antique Persian mirror, paralleling an incident in a newly published fantasy novel Boxlands, which was inspired by the childhood stories of C.S. Lewis (after whose book this episode is named). When the author's fiancée finds her life under threat from a shadowy stalker, Lewis suspects that the first murder was a case of mistaken identity, and must work fast before the killer returns to rectify the mistake.

A preview performance of a student production of The Merchant of Venice is cut short when the actor playing Shylock is stabbed to death with a prop knife. The victim was a womaniser and drug-user who, when he could not borrow money, stole instead. Lewis and Hathaway are working their way through a lengthy list of suspects when another person connected to the play is killed. In a separate investigation involving a con man, Hathaway faces a dilemma involving Lewis's past.

Lewis and Hathaway look into the murder of a man found beaten and drowned in his bath, with massive burns due to the boiling water. The deceased is identified as a man who once attempted to murder Tom Rattenbury, a celebrated atheist, but instead crippled Rattenbury's daughter, Jessica. The investigation is not helped by Rattenbury's ambitious and over-protective wife. A Renaissance painting, The Hunt in the Forest (also known as The Hunt by Night or simply The Hunt) by the Italian artist Paolo Uccello, is a key clue in the mystery. It is perhaps the best-known painting in the Ashmolean Museum, Oxford, England.

An ageing pop star causes complaints when he fires off his hunting rifle and disturbs the local Sunday service. When he goes to caution him, Lewis is shocked to encounter Esme Ford, a rock singer he had once admired, who was believed to have drowned years ago. The body of a teenage boy, who has been repeatedly run over by a vehicle, points to a connection with members of Esme's old band.

After a body is found on an Oxford tour bus, Lewis and Hathaway are led to Crevecoeur Hall, a sprawling Oxford estate where Hathaway spent much of his childhood.

When Andrew Crompton, amateur astronomer and Master of Gresham College, is found dead at the foot of the University Observatory stairs, Lewis and Hathaway find that the finger of suspicion points at all the staff - from tutors right down to the head porter and the college scouts. Lewis uncovers a college-wide blackmail plot and is confused by a mysterious astronomical conundrum. Hobson is unexpectedly drawn into the case while rehearsing for a performance with a local orchestra at the college.

Over an August bank holiday, an empty Oxford college is the venue for a weekend attended by professional quiz contestants. Though both have personal plans for the weekend; Lewis going out of town to attend a play, and Hathaway a rock concert, they are called in when outstanding competitor Ethan Croft is found floating dead in the college fountain. They learn that Croft was an outrageous flirt with a number of secrets, and the pair race to uncover the killer before the gathering breaks up. Meanwhile, Hathaway discovers that Lewis was planning a romantic weekend at Glyndebourne with a mystery date. On the side Lewis assists Hathaway in retrieving his vintage Gibson guitar, which was stolen from his car while at the rock concert.

On Halloween night, a university friend of pathologist Laura Hobson is found staked through the heart. During their investigation, Lewis and Hathaway are approached by a medium who claims that they are in grave danger. The following day a student is murdered in the house that Hobson shared with her university friends, and a clue at the crime scene leads Lewis and Hathaway to a third victim. As the body count rises Lewis and Hathaway are forced to acknowledge that Hobson might know more about the deaths than she is letting on.