Seven-day TV guide

Bodyguard

(BBC1, Sunday, 9pm)

IT was clear right from the first episode’s tense opening sequence, in which soldier-turned-Specialist Protection Officer David Budd (Richard Madden) realised there was a would-be suicide bomber aboard his train, that Bodyguard was going to keep viewers hooked.

The ratings confirmed it – the first episode was watched by 10.4 million viewers, the best showing for a new British drama since 2006, and it also set a record for iPlayer requests.

The series hasn’t let up since, with some literally explosive scenes, as well as a shocking twist in the fourth episode that had countless viewers sharing their theories online.

If you’re one of the few people who isn’t on tenterhooks ahead of this final episode, the series, which comes from Line of Duty writer Jed Mercurio, follows David, who is given the job of protecting Home Secretary Julia Montague (Keeley Hawes) as she lays out some controversial plans for dealing with the threat of terrorism.

To make her bodyguard’s job more difficult, it becomes increasingly clear that Julia has also made enemies among her own colleagues, who resent her ambition, and the police, who don’t appreciate her cutting them out of loop.

And then there’s David himself, who is still dealing with the trauma of his wartime experiences – and the knowledge that Julia is unrepentant about voting to send him to war. As the series has progressed, it’s not just the viewers who have been asking if David might actually be the biggest threat of all

If you’re not sure who to trust, Mercurio is doing his job. He says: “I think it’s very important, if you’re doing post-watershed drama for a discerning audience, that you make it distinctive.

“A lot of TV does go for heroes and villains – and for very demarcated characters. One of the characteristics of Line of Duty and Bodyguard is that characters can have a bit of good and evil in them. They can be positive characters with very real flaws that lead to dramatic consequences.”

But he thinks the series’ other big selling point is the action: “One of the centrepieces of the story is the terrorist threat and unfortunately that’s something that we’ve all learned to live with in our big cities. It’s very contemporary and obviously we want to handle that in the most sensitive way, but also in a way that does feel authentic.

“We have a number of big action sequences within the series and that’s really part of the appeal of it, I hope.”

But just how much more action will we be in for tonight, as David goes in search of the truth about the attack on Julia?

It’s clear not everyone appreciates his interference in the case, especially as the evidence against him continues to mount up.

Can he prove his innocence – and will any of the online theories about who is pulling the strings be proved correct? What we do know is that there are so many loose ends to tie up that the Bodyguard is concluding with an extended episode.