BODYGUARD has the nation totally gripped and there are two things that everyone wants to know: who planted the bomb and did Julia Montague survive the blast?
Here are the latest theories and predictions, and when you can catch episode five of the BBC hit.
When is Bodyguard on BBC One?
Bodyguard kicked off on Sunday, August 26. In the first episode we were introduced to Army veteran and now close protection officer David Budd (played by Richard Madden) and the woman he is charged with guarding – the ambitious Home Secretary Julia Montague (Keeley Hawes).
Episode three saw Budd and Montague being caught up in an explosion at a London university as the Home Secretary tried to rally support for her divisive new security policy.
The following episode focused on the aftermath of the blast and the investigation into how the explosion was allowed to occur as police tried to identify the bomber.
Episode five airs on Sunday, September 16, at 9pm on BBC
Each episode becomes available to watch via iPlayer shortly after broadcast.
Is Julia Montague really dead?
After a previous attempt on her life when she was fired upon by a sniper in central London, Julia Montague refused to be cowed and at the end of episode three headed to a university in London to deliver a speech to boost support for her controversial RIPA-18 security and surveillance reforms.
But it also appeared she was using the major address to outline her desire to run for leader of her party and become Prime Minister.
As she approached the key part of her speech, a huge explosion ripped through the stage leaving several people either injured or dead.
In episode four the PM, whom Montague met with secretly at Chequers just before the blast, announces to the world she has died as a result of the injuries suffered in the explosion.
But fans are not convinced Montague, who has become romantically involved with her bodyguard Budd, can be dead.
IMDB, the respected movie and TV database, has her listed as appearing in five out of six episodes of the BBC drama.
It is thought she will not appear in episode five but will return in the series finale – which looks set to be one of the TV events of the year.
Appearing on Good Morning Britain, Stuart Bowman, who plays the shadowy MI5 chief in Bodyguard, refused to confirm or deny whether Montague was really dead.
“You don’t really want to know,” he told Piers Morgan and Susanna Reid.
Who planted the bomb at Julia Montague’s speech?
The explosion which occurred at the Home Secretary’s speech was a significant one and preliminary evidence suggests the device was of a similar nature to two other bombs which have featured in the show previously.
While security services and the police hunt for a suspected bombmaker who is still active in London, everyone is asking – who was behind the bombing, and why.
Here’s a look at some of the potential suspects:
Many people’s favourites for the crime, the security service have been behaving in a highly suspicious manner throughout the series.
Questions over their intentions were initially raised as they struggled to share information with the Met’s counter-terror police over the failed 1/10 bomb plot on the Euston-bound train.
Then there was the mysterious visit to the hotel of the man who identified himself to Budd as Richard Longcross – almost certainly an alias.
Longcross was later seen telling MI5 chief Stephen Hunter-Dunn that Montague had met secretly with the PM, causing Hunter-Dunn to react with anger and indignation.
It could be that MI5 have grown suspicious of the threat posed by Montague and fear being cut out of the loop over vital securtity issues.
Equally they could have arranged the bombing in order to increase support for her criticised plans to increase the snooper powers of the security services.
A special adviser to Montague, Rob MacDonald is a key person in the investigation into the bombing for one major reason – he was the man who gave the briefcase, which some think contained the bomb, to Tahir Mahmood to take to the London speech.
He then chose not to travel with Montague to the event, which investigating officers remarked was very unusual.
MacDonald also wilted during his interview with the police and aroused further suspicion when he said “we” instead of “I” as he discussed returning the briefcase.
Anne Sampson and the Met Police’s counter-terrorism force
Anne Sampson, who heads up the country’s counter-terror forces, was livid after Montague, who had grown tired of police failures to make progress on previous terror attack investigations, granted greater investigatory powers to the security services.
Mike Travis, who is promoted to acting Home Secretary in the wake of the bombing, then puts the Met back in charge of the investigations, pleasing Sampson.
It then appears she gives Travis a heads-up when MacDonald becomes a target of suspicion.
The Prime Minister/ Chief Whip Roger Penhaligon
No 10 is shown throughout the series as growing increasingly suspicious of Montague’s actions amid fears she is mounting a leadership challenge.
Roger Penhaligon is the Chief Whip as well as being Montague’s ex-husband – on several occasions, he demonstrates his hostile relationship with Montague.
Then there is the Home Secretary’s mysterious late-night visit to Chequers to meet with the PM.
Prior to the meeting, she demanded Budd call off all other protection officers on her case and that he drive her to Chequers himself.
Was this a request from the Home Secretary, or a demand from No 10?
Could Budd, who is caught between his loyalty to his job and his anger at Montague for supporting military intervention overseas, have carried out the attack himself?
It is certainly possible especially when you factor in his enduring PTSD and nightmares, not to mention the horrifying moment when he choked Montague in the hotel.
Viewers were sent wild when Budd inspected the suspicious briefcase moments before the attack on Montague.
Despite giving it the all-clear and saying it contained nothing but documents, viewers were not shown the contents of the briefcase for themselves.
Could Budd have intentionally missed the bomb, or even planted it in there himself?
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Two previous bombings have already occurred in Bodyguard, the failed suicide bombing on the train and the truck attack and bombing near Budd’s children’s school.
Initial investigations show that all three explosive devices were manufactured by the same bombmaker and that that terrorist was still at large.
While Budd and the police interview Nadia, the woman who attempted to carry out the 1/10 train bombing, she has yet to give them any names to investigate.
Also during a crisis meeting following the blast at St Michael’s, viewers are told that IS have tweeted in reference to the attack – although the terror group failed to claim direct responsibility for it.
Chanel Dyson – the fired PA
One of the most interesting theories involves Chanel Dyson, Montague’s former PA who was fired early on in the series.
Clearly angered by her dismissal, she went to a reporter in the hope of smearing Montague and damaging her leadership aspirations.
Following this meeting, she was picked up on the street by a mysterious black Range Rover and, reluctantly, got inside.
Could Dyson be a double agent or have blackmailed into betraying her former boss?
Currently the chief suspect for police investigating the attack on Montague, Mahmood was only recently brought onto the Home Secretary’s team.
Moments before the explosion he made his way onto the stage near his boss and is assumed to have died in the blast.
He also received a telephone call just minutes prior to the blast from Rob MacDonald, which MacDonald claims was just him enquiring how the speech was going.
While police interrogated Nadia, they showed her a picture of Mahmood and asked her if she recognised him. While she said no, her eyes did appear to linger over his photo before flashing up to Budd’s.
It sounds far-fetched, but what if the Home Secretary, desperate to push through her RIPA reforms, organised the blast herself to increase public and Parliamentary support for her heightened surveillance laws.
Her behaviour has been suspicious from an early stage. She was given an encrypted tablet device by the mysterious Richard Longcross in the hotel and has been reviewing secret dossiers on it.
Then there was her meeting at Chequers with the PM, as well as her desire to reinstate Budd to her protection unit.
Plus her desire to make a high-profile public appearance at St Michael’s flew in the face of the advice of her security detail, who were eager for her to avoid public places while the terror threat remained high.
Also, surely only someone high up in the intelligence community could have arranged for Budd’s house to be searched and replace the bullets in his gun with blanks.