5 unanswered questions we still have after the Endeavour finale

With several storylines that stretched across all three episodes, by the end we finally discovered who the towpath serial killer was - and whether Endeavour was right when he began speculating that a sequence of freak accidents weren't so accidental after all.

But with so many threads to tie-off by the end of the third episode, you'll be forgiven if you still had a few queries about how the show ended - and what lies in store for the detective...

Who was the towpath killer?

Fred Thursday's instincts were proven right all along, after Carl Sturgis (the jealous boyfriend of the killer's original victim, Molly Andrews) was revealed to be the towpath serial killer. He murdered victims Molly, Tony, and Bridget - although we'll admit, we're still unsure whether the episode entirely resolved the plot-hole that Endeavour himself pointed out; namely, Carl's iron-cast alibi from the original night in question.

Not only was Carl identified as the towpath killer, but he was also revealed to be the violent (and cannibalistic) brother of Jenny Tate, a waitress with the gift of foresight, who was previously introduced earlier in the series. Turns out that both of them escaped a house fire when they were children, although it's not quite clear where Carl has been all these years.

Was there a copycat killer?

Yes. The masked man who attempted to strangle a fellow of Lady Matilda’s College, before being chased onto a road and into the path of an oncoming car, was in fact a copycat killer.

Endeavour realised that he'd been whistling a tune different to the one that the real killer whistled as he approached his victims.

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Is DS Jim Strange dead?

After following up on a tip from Endeavour, it was dependable Jim Strange who discovered Jenny tied up (and covered in bite marks) upstairs in the empty house where Carl was staying. Carl stabbed Jim, who collapsed on the floor as Endeavour arrived on the scene.

The last time we saw him on-screen, he was being stretchered off to hospital. But given that an older version of the character stars in the original Inspector Morse series (starring John Thaw), somehow we think Jim will survive.

Who was causing the 'freak accident' deaths?

Endeavour's loveable and eccentric friend Ludo (whose wife, Violetta, Endeavour was having an affair with) turned out to be much less clueless than we originally thought. He was revealed to be the mastermind behind a widespread and deadly life insurance scam, which Endeavour first cottoned onto when he discovered a pattern of supposed 'freak accident' deaths across Oxford and beyond.

The only factor that linked all the deaths was that they had all recently sold off their life insurances schemes, meaning that if they suddenly died (or, as it turned out, were murdered), the money that should have gone to their grieving families instead went to the mystery buyers (Ludo and Violetta).

Endeavour managed to catch up with them both in Venice, where his romance with Violetta first began at the start of the series. Ludo was shot by Fred, who had tailed Endeavour without his knowledge, while Violetta threw herself in front of a bullet meant for Endeavour. She then declared her love for him – "Ti amo" – and died in his arms.

Is Endeavour leaving Oxford - and Fred?

Following a huge bust-up between Endeavour and Fred, the former decided to transfer to a different police force. Things remained frosty between them for most of the episode, until Fred - at wife Win's urging - dropped round his house on Christmas Day, and found the house empty. He returned home to find that Endeavour had posted a letter to Fred's daughter, Joan.

Opening the letter, Win and Fred found enclosed papers proving that Ludo was behind the spate of freak accidents - along with a letter to Joan, in which Endeavour admitted that the breakdown of his relationship with her father had been his fault alone.

The last we saw of the pair, Fred had just saved Endeavour's life in Venice. But while actions speak louder than words, can some things never be unsaid? Can Fred forgive his protégée for his cruel words, and will Endeavour be too proud to go back on his pledge to leave?