Trigger Point continued to present audiences with many twists and turns during Sunday night's episode – and it seems the most recent instalment left many watching at home a little confused.
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After the previous episodes pointed to Lana Washington's (Vicky McClure) boyfriend DI Thom Youngblood (Mark Stanley) being the potential "inside man" who was building bombs, episode four painted out another potential bad guy, ex-Military officer Karl Maguire (Warren Brown).
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Audiences were then confused about who is really behind the string of bombings, as one person summed it up on Twitter: "Is Karl or Thom the bad guy… one of them has to be the baddy, right? I called Thom at the start but now I'm confused. #TriggerPoint What an incredible actress @Vicky_McClure is!!."
A second fan was also unclear on what's about to happen and tweeted their theories: "Karl is either A) part of the terror cell or B) The next bomb victim of Young Blood and John. That's my conclusion... at week four. May all change next week. #TriggerPoint."
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Viewers couldn't work out if Karl was the real baddie
A third said: "Absolutely brilliant show! I've [gone] from blaming Youngblood, to Karl, to John but settling on Inspector Lee! #TriggerPoint."
Viewers watching at home, as well as lead character Lana, are convinced the culprit has to be an inside man on the job due to the techniques used to create the bombs – hinting that a professional has been behind the string of attacks all along.
The official synopsis from ITV reads: "Reckless and out of control, Lana is ex-military and pushed to breaking point dealing with a series of improvised explosive devices which threaten the capital during a terrorist summer campaign.
"Under extreme pressure and searching for answers, Lana can't help but become suspicious that the bomber is premeditatedly targeting her unit. It's a terrifying thought, but against all odds, how does she prove it and discover the bomber's real identity?"
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