Bodyguard fnale: Smash-hit BBC drama ends with a twist as viewers finally find out who murdered Julia Montague

Tom Powell
Detective sergeant David Budd: BBC/World Productions/Sophie Mutevelian

BBC One hit drama Bodyguard has ended with a twist revealing who was responsible for the death of Home Secretary Julia Montague.

The six-part Jed Mercurio political thriller concluded with a revelation about the fatal explosion which killed Keeley Hawes's character.

It was revealed that Nadia Ali, the thwarted terrorist from the first episode, created the fatal bomb.

She was working with criminal Luke Aitkens, who was aided by police insider CSI Lorraine Craddock.

(BBC/World Productions/Sophie Mutevelian)

The revelation came at the end of a tense episode which saw Army veteran and close protection officer Sergeant David Budd, played by Richard Madden, himself strapped into a suicide vest.

Budd finally presents himself for counselling for his PTSD, and the finale hinted at a happy ending for the bodyguard and his wife.

Montague was planning to push through laws which would give security services "more of an upper hand" against organised crime.

This motivated Aitkens, who was said to need corruptible police to stay safe from prosecution.

Ali was revealed to have passed on information about Budd's children and to have been behind all the bombs used to wreak havoc.

(BBC/World Productions/Sophie Mutevelian)

She said: "I'm a jihadi."

Ali revealed that she provided the bombs to Aitkens for money to fund further terrorist activity.

An encounter with Aitkens left Budd strapped into a suicide vest, leading to a dramatic standoff.

Richard Longcross was arrested after triggering a trap left by Budd, whose wife was watching on as he stood in the explosive vest.

But his suspected involvement was a diversion by Ali.

Killed off: Julia Montague died of injuries sustained in a blast ripping through a conference she was speaking at (BBC/World Productions/Sophie Mutevelian)

Head of MI5 Stephen Hunter-Dunn was also watching the showdown and seen to be plotting to frame Budd with the help of Mike Travis.

The release of the kompromat tarred Hunter-Dunn's reputation and that of the Prime Minister John Vosler.

Vicky Budd bravely joined her husband, leading police to cancel an order for a fatal shot and unearthing the kompromat.

Budd unstrapped himself from the lethal vest in a nerve-wracking scene.

Craddock met with crime kingpin Aitkens, who said the assassination was "nothing personal".

In the closing scene of the episode, Budd is seen driving off with his children and his wife.

The first episode attracted 10.4 million viewers and dominated the audience share, according to the BBC.

These are the highest figures for a programme launch since 2006.