Can Rachel Duffy – traitor extraordinaire, smiling assassin and FBI-trained detector of lies – do it?

Spoilers ahead if you’re not up to speed on The Traitors UK, but it’s not looking great. At the conclusion of last night’s penultimate episode, the head of communications and mother of three from Newry was in deep trouble, and that’s a huge shame.

Rachel has lit up this series of the reality competition show. The standout traitor and best value cast member all round, she has effortlessly understood the assignment.

She has married the art of survival to a knack for meme-worthy reactions, while not being afraid to inject a note of drama into proceedings. She has seen off 16 of the 22 contestants, including two key adversaries, while staying more or less united – so far – with fellow traitor Stephen Libby.

But now, despite her many wiles, only luck can save her. After an unresolved deadlock at the round-table, and with the vote tied between Rachel and faithful James Baker, the outcome of the latest banishment was to be determined by the Chest of Chance.

Alas, the episode ended on the Cliffhanger of Calamity, and viewers must wait until tonight’s final on BBC One at 8pm to discover if Rachel is toast.

The suspicion must be that producers know she is the MVP (most valuable player) of the series so have postponed showing her departure. Even if she has saved herself by picking the chest containing the protective shield, she now has enough heat on her to make victory in the endgame seem unlikely.

But who knows? The Traitors editors have fooled us before.

Rachel first walked into Ardross Castle in the Scottish Highlands in a pink netted skirt that belied her toughness and resilience.

“There’s nothing I won’t do to win a game. I work in communications, I’ve three kids, I know how to negotiate, I just have a tendency of knowing the right thing to say and how to get what I want,” Rachel said.

Soon she was standing in front of a Latin transcription and jokingly translating it for the benefit of another contestant as “Rachel is going to win this”.

It quickly became apparent that this wasn’t just a joke. Rachel was armed with the confidence of someone who had been trained by a former FBI agent “on the beauty of micro-expressions and people’s ability to lie”. She later revealed this to the others, recasting it as her way of serving as a dedicated traitor-hunter.

In fact, tapped on the shoulder to become a traitor by presenter Claudia Winkleman in episode one, she had swiftly warmed to the task of “murdering” people in the game.

Rachel knew that if you went on this show and weren’t looking forward to outwitting people through deception and gameplay, then you had applied to be on the wrong show.

“You feel bad when you’re playing people, but it’s the nature of the beast,” she told viewers.

On a recent Instagram video she thanked fans, including supporters in Newry who have made her laugh by shouting “ya big traitor” in her direction. Still smiling, she also calmly reminded “anyone who might have forgotten” that The Traitors is a game and 22 people had “signed up to be lied to and deceived”.

Along the way, Rachel has been cut-throat, but funny with it. She has been clever, but she hasn’t taken a strategic back seat.

For a long time, she was more suspicion-proof than Stephen, her longest-lasting co-traitor. He has visibly panicked more than she has, but he now looks to be in a stronger position to win. It makes sense. As a cyber security consultant, he must surely be able to detect threats.

Back in episode five, the misguided trust that the cast had in Rachel took a hilarious turn when Amanda Collier, a faithful, confided in her about her former life as a police detective. Rachel smirked, but did not blink.

The incident prompted traitor Fiona Hughes to accuse her of lying, but Rachel just shook her head in disbelief and gleefully told everyone else about this bizarre attack on her character. Fiona was soon gone.

When Harriet Tyce, a faithful, declared her intention to go after Rachel at the round-table, she “scared the life” out of her. But the crime novelist and her breakfast-table “truth bombs” scared too many other people, and Rachel, unleashing the battle-cry “bring it on”, emerged victorious from that chaos, too.

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As the final week began, every tactic or piece of guesswork was coming off for Rachel and Stephen. On Wednesday, they secretly gave the power of the ceremonial dagger – a double vote at the round-table – to James, anticipating that the blame would be pinned on faithful Matthew Hyndman. That’s exactly how it played out and Matthew, originally from Derry, was banished.

Rachel has said that if she wins the potential prize pot of £120,000 she will use it to “make memories” with her mother, who has dementia, and her children. But she also applied to the show to “have a little bit of fun, and that’s exactly what it should be”.

She’s right, and credit is due to the producers who cast her and gave her such a prominent role. Through her lies she has proven the truth of this show. As viewers we root for the traitors and invariably want them to win.