Speaking previously about series three, Dornan said: "You can expect the unexpected. There's quite remarkable turns in the third season that I really genuinely think people won't see coming that are hugely exciting."
This series got off to a rocky start with many comparing it to a medical drama after a lengthy opening episode focusing on the hospital treatment for Spector.
The serial killer claims he can't remember any of the heinous crimes he has committed and thinks he is in 2006 - but will a quizzing from Stella tonight jog his memory?
The trailer for Thursday's night instalment hears Gibson say: "Drop the charade Peter, you remember everything".
Who do you think will win the final fight between Spector and Stella?
The final two episodes will air on Thursday October 27 and Friday October 28 at 9pm on BBC2.
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