This review contains The Replacement finale spoilers.Praise be for the three-parter. Even when the narrative wheels come off, as they did in spectacular fashion in The Replacements ludicrously overblown finale, youre still quids-in when it comes to your time investment. A dodgy last hour after two decent instalments is forgivable, especially when its all so bonkers you cant look away.Episode three put pay to all the subtle ambiguity over who was really the crazy one and vindicated our girl Ellen by exposing Paula not only as Kays killer but also as the villain from the Saw films. The blue-eyed monster hatched a plan so complicated that even after watching the episode twice and taking notes each time, I could still use a steer on what actually happened.Heres what I have so far: Paula wanted to save baby Lia from Ellen, so stole the former from a windowsill like a pie in a Yogi Bear cartoon, then sent a cryptic message to the latter inviting her to the place where she died. (Reading she as Paulas daughter Caris, Ellen met her foe at the accident site though if shed done what I did and interpreted she as Kay, it turns out shed have driven straight to baby Lia without any need for all that A-Team nonsense in the garage).If Paula planned to fake Ellens suicide and then take her place as Lias mother, then what about that whopping filing cabinet leaning against the car, or Paulas line about knowing she couldnt have Lia? If she planned to frame Ellen as Lias kidnapper and be the one who marches in with the police and saves the day, then why quietly accept the handcuffs? Was Ellen supposed to wake up from those sleeping pills? Did Paula turn herself in to the police? Forgive me if its all clear to you, but Im genuinely floundering.Kudos to Vicky McClure and Morven Christie, whove gone up in my already high estimation by gamely selling whatever it was that happened in those last ten minutes. Theyre such good actors, they even had me convinced they had a clue as to what on earth was going on. That pair were The Replacements prize; the depth of their performances kept this story of well-dressed unhinged women from venturing too close to soap territory.Until this episode, that is, when it held its nose and took a running both-feet jump into soap-land. Dead Caris being kept alive as a comforting lie? The faked push down the stairs at a chichi party? Paula breaking up Ellen and Ian by telling him Lia isnt his baby? Colour-drained flashbacks to seemingly incriminating dialogue? Is this a BBC psychological thriller or Days Of Our Lives? Georgias child has leukaemia, we learn. And an evil identical twin no doubtIt probably didnt help the accusations of soapishness that the cast was so uniformly good-looking. Everyone, from Ellens sister to the mysterious Georgia to those social workers, looked like Abercrombie and Fitch models. Theres not a pot belly, imperfect smile or pair of eyes you wouldnt want to dive into in the whole joint.In the finale, all the nuanced tension and promised exploration of competitiveness, paranoia and what work and motherhood mean to modern women went out of the window (or should we say through the skylight). With that absurd MacGuyver ending, it blew it. Ultimately, The Replacementturned out to beyour average bereavement-turns-mothers-into-psychopathic-murderers thriller, nothing more complex or original than a posh soap with a partiality for contra-zoom camera tricks.Still, those two were great leads. You have to give it that.The Replacement is streaming now on Netflix UK.Join our mailing listGet the best of Den of Geek delivered right to your inbox!