Bodyguard episode 4 recap: Thriller produces another stunning plot twist

Yes, our female lead is no more. This thrilling, whip-crack drama phenomenon that has kept up the unbearable tension, while surprising and stunning us at every turn will have to do without her. Just about anything seems possible now.

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But the first question to be asked is this: is Julia actually dead? Yes, we saw what one presumed were her grieving parents being told the bad news by the hospital consultants. It was announced live on TV by the Prime Minister and reported, no doubt around the globe.

But this is a high-octane work of fiction, a political thriller where anything is possible. Her death could, conceivably, have been faked as part of some high-stakes ruse by the security services. To smoke out the culprits perhaps – monitor chatter when everyone thinks she is dead, swoop on the suspects and reveal that the whole thing was made up in order to achieve the ultimate goal of foiling a terrorist cell. I know it sounds far-fetched but the politicians could get away with that. Or they might try?

Now this seems hugely unlikely but it’s a measure of the brilliance of this drama that anything is on the table in murky world of Whitehall manoeuvrings, missing hotel tapes, and political and ideological agendas firings at us from every side.

We never saw her body. And Mercurio, the master of misdirection, does have form in bringing Keeley Hawes back. The shock return of her Lindsay Denton in Line of Duty – from prison and obscurity, admittedly and not the grave but brought back nonetheless – should give us pause. He may do it again.

In episode four Mercurio even flirted with the idea of killing off David Budd. Just after the news of Julia’s death was announced we saw him blow his own head off, the drama thus seeming to dispatch the two main characters, the eponymously bodyguard and his politician lover, in one hour.

But what Budd fired into his head was a blank – the shard in his head was the copper casings of a duff bullet. Which of course opened up yet another twist. Someone, Budd realised, had replaced the bullets of his own weapon which he had hidden in his flat. Someone had found the firearm – but he hadn’t been hauled in (owning an unauthorised gun is a very serious offence). So who dun it? Security services you’d think. Security services David Budd certainly thinks. But you never know.

Currently the investigation’s attention is focused on Rob McDonald (Paul Ready), the Home Office aide who had been caught on CCTV swapping briefcase with Tahir Mahmood, the man suspected of being the person who carried the bomb into the auditorium where Julia was fatally wounded.

Mike, the acting home secretary, had a very fishy conversation with Rob about keeping quiet about something – so something's up there.

And is Tahir the bomber? He was certainly not picked out by Nadia (the would-be suicide bomber from episode one) when she was interviewed by Budd. Is Budd behind the whole conspiracy? Was his suicide a mark of regret at killing the woman he realised at the end really did love him? Attention is certainly focusing on him as he walked away at the close, allowing the audience to finally catch his breath.

"I don’t trust him,” said detective Sharma. “He’s hiding something.”

Well at least that’s one thing we know to be true.