Line Of Duty star Nigel Boyle has defended the series six finale, after fans took to Twitter in droves to express their disappointment.
Fans across the nation were left underwhelmed and disappointed on Sunday night as the nail-biting series finale drew to a close - and the mysterious antagonist 'H' was finally unmasked as DSI Ian Buckells, played by Boyle.
And during an appearance on BBC Breakfast, Boyle insisted that viewers of the hit show would grow to appreciate the ending over time, as they look back at the clues.
He said: 'The fans have been brilliant. So many people have invested so much in this series, and some of the fans' theories themselves have been outstanding.Insurance Loans Mortgage Attorney Credit Lawyer
'So I think there's always gonna be some element of disappointment, but you can't have every series with a big shoot-out, urgent exit required.
'Sometimes the subtler message is more important. I sent a tweet out after the episode last night and I jumped in a car and came straight over to the studios, so I didn't really look at social media.
'I think when people reflect and they get back to work tomorrow and start talking about it, I think some people won't be as disappointed.
'I think with this season more so than the other seasons, people have been watching it not just once, but two or three times and really analysing what's going on.
'And I think when you watch this again, I think you'll reaffirm some assumptions and you'll see things that you might not have seen.'
Loyal viewers took to social media in their droves to share their frustrations as officers from the police anti-corruption unit AC-12 discovered the identity of the elusive 'fourth man'.
But the revelation the bent copper colluding with the organised crime groups (OCGs), was actually DSI Ian Buckells infuriated many seasoned Line Of Duty fans.
It saw the words 'fuming', 'disappointing' and 'underwhelming' all trend on social media in the aftermath of the show.
And the disbelief it could be him was compounded by the way he was only caught because of his repeated mis-spelling of the word 'definitely' - hardly the blunder of a hardened criminal mastermind.
The detective - widely thought until last night to have been just a bungling stooge - was first introduced to viewers in series one as the SIO in the case of murdered businesswoman Jackie Laverty by then Chief Superintendent Derek Hilton.Insurance Loans Mortgage Attorney Credit Lawyer
He later went on to become Detective Chief Inspector in series four before being promoted once more to Detective Superintendent in this final series.
Sharing their disappointment on the revelation, one disgruntled Line of Duty fan wrote on Twitter: 'Can't believe I watched six seasons of line of Duty for Ian Buckells, the most pointless character to be the fourth man. Fuming.'
While another viewer added: 'I'm fuming, can't believe I waited this long for Ian Buckells to run the roost.'
And while the finale tied up many unresolved storylines, there were still some gaping plot holes and storylines left unanswered.
They included:Why did Buckells ordered the attempted murder of DCI Jo Davidson, when she was under the mistaken belief H was actually another dirty former police chief, DCS Patrick Fairbank? Why was Davidson was also given a luxury life in witness protection - despite the fact the intelligence she delivered was completely wrong? Who was the real leader of the OCG, as Buckells insisted it was those groups who tasked him to carry out his corrupt crimes? With Buckells inside prison at the time, who forged DS Lomax and DI Fleming's signatures to authorise Davidson's dodgy prison transport ? Chief Constable Philip Osborne spent the series blindly denying corruption in the police force, yet why was it that when it was proved there were bent coppers in the force it had no consequence for him? Now that Hastings has come clean about his accidental role in an undercover officer's death, what will this mean for his appeal against his forced retirement? Given Buckells' closeness to many of the villains from previous series, why did AC-12 fail to investigate him further earlier in their corruption probe?
Line Of Duty's much-anticipated sixth series came to its conclusion on Sunday night with the identity of the elusive criminal 'H' finally unmasked
Fans shared their frustrations as officers of the police anti-corruption unit AC-12 discovered the identity of the elusive 'fourth man'
The sixth series of the Jed Mercurio creation also saw DI Steve Arnott, played by actor Martin Compston, finally called in for a meeting with Occupational Health, who noted that while he had not broken the law through his excessive painkiller use, he would have to surrender his firearms licence.
However, the 60-minute episode's end failed to offer any resolution on whether the fan-favourite team of DI Steve Arnott, DI Kate Fleming and Superintendent Ted Hastings would return, ending on the revelation that the team has 'never been weaker.'
The mystery surrounding the identity of 'H' has been up for speculation since his character was first mentioned at the end of series three, which aired in 2016, and detectives at the anti-corruption unit discovered there were four officers working within the force who had links to the underground criminal network.
But fans slated Buckells as the fourth man, with one complaining: 'We waited 10 years for Ian Buckells to be revealed as the OCG mastermind.'
Another commented: 'Everyone in the UK when we waited all this time for Ian Buckells to be revealed as the OCG mastermind.'
Meanwhile another fan said: 'I would have accepted Hastings as H over Ian bloody Buckells #LineOfDuty #LineofDutyFinale.'
Elsewhere another viewer added: 'I once got the entire UK invested in a TV show only to end it with bumbling Ian Buckells being H #LineofDutyFinale #LineOfDuty.'
And another wrote: 'Well I hate to say it but that's a disappointing ending. I refuse to believe it was all down to Ian Buckells of all people.'
There from the start: Buckells was in series one of the hit show, which concentrated on the story of compromised Tony Gates
A series 4 return saw him involved in the storyline starring Thandiwe Newton as Roz Huntley as main corrupt officer
Series six saw Buckells - played by actor Nigel Boyle - returned for his biggest role in this years' episodes and a starring role
One frustrated fan added: 'In whose universe is Ian Buckells any kind of mastermind of anything? I'm dazed and completely confused.'
Sharing their disappointment, another viewer wrote: 'Ian Buckells?! Seriously? Surely there has to be a bigger twist in the next series? The man couldn’t tie his own shoelaces, let alone be a criminal mastermind#LineOfDuty #LineofDutyFinale #letdown.'
During the episode tonight, which saw around 12million viewers tune in, Superintendent Ted Hastings, played by actor Adrian Dunbar, was seen asking his colleague Chloe to run checks on the constant misspelling of the word 'definitely' as 'definately' which had become synonymous with the 'fourth man' in previous episodes.
Viewers were introduced to the misspelling when the mysterious 'H' sent a message to former undercover officer John Corbett, played by Stephen Graham, in series five.
A number of checks that looked for idiosyncrasies in grammar, punctuation and spelling traced the word back to Buckells who first used the misspelling in a report during the Lawrence Christopher investigation in 2003.
When confronted with the revelation Hastings was left astounded, asking his colleague: 'Are you sure Chloe?'
The revelation set the stage for a dramatic confrontation between Hastings' team and Buckells who eventually confessed: 'Yeah right I'm a blundering fool. I'm only the one whose made total mugs out of you lot!'.
He also revealed the police would have to offer him immunity or Witness Protection if they wanted him to co-operate, telling the AC-12 team: 'DCS Carmichael is meant to be taking over isn't she? But she ain't in here. So that makes me wonder whether she doesn't want to associated with detecting institutionalised corruption.
'Because officially institutionalised corruption doesn't exist does it?
'Officially 'H' or the 'Fourth man' or whatever you want to call him, he don't exist neither. So that makes me realise that everyone would be much happier if this all just went away. So I'll take Witness Protection and Immunity.'
Pointing out that H did not officially exist as the investigation into corruption had been quashed, he went on to say Tommy Hunter, the organised crime kingpin who was a sinister character during the drama's early series, was the leader of the OCG.
Also during the show, viewers watched as DI Arnott was left torn on whether to pursue fears that his boss Ted Hastings could be the elusive 'H' as the team raced to uncover the mystery figure's identity.
The officer also admitted to his detective friend Kate Fleming, played by Vicky McClure, that he had been involved with former undercover officer John Corbett's widow Steph.
As the team from AC-12 tried to unravel the mystery surrounding journalist Gail Vella's death, who was shot dead earlier during the series as she investigated connections between the police and the OCG, they found a strong box hidden under the floor of the criminal organisation's workshop.
Social media fans were left far from impressed with the identity of the elusive 'H' as the series drew to a close
DSU Ian Buckells was first introduced to viewers in series one when he was appointed as SIO in the case of murdered businesswoman Jackie Laverty
Buckells, who was revealed to be the elusive 'H' tonight, speaking with detective Kate Fleming in series four of the drama
The box was revealed to contain an array of weapons used in murders investigated by Hastings and his team, including the gun that shot and killed Vella, and the knife that slit the throat of DS John Corbett, who was killed by the OCG in series five.
It was the breakthrough that the team had been waiting for, as the box finally proved that Carl Banks, the violent criminal who also goes by the name 'Ross Turner', was responsible for Vella's murder before being killed by the OCG himself.
After weeks of incessant emails, DI Arnott was finally called in for a meeting with Occupational Health, who noted that while he had not broken the law through his excessive painkiller use, he should take time off from his duties.
It came after the detective was seen ignoring the reminders dropping in his inbox to book an appointment for a routine drugs test.
The officer, who became addicted to painkillers after he was pushed down a flight of stairs during a police operation in series four, refused to step down from his duties but did agree to hand over his firearm.
He also came clean to his boss Ted Hastings about his drug use and to his, and the viewers' surprise, Hastings did not dismiss him, simply saying: 'I'm glad you're getting some help.'
Despite fans' theories that James Nesbitt's character Marcus Thurwell had to be alive, it was revealed that he was killed in the previous episode, and had actually been dead for several weeks when his body was found after being strangled.
It came after the penultimate episode showed the Guardia Civil police officers storm his Spanish home and find two bodies on the bed.
DC Chloe Bishop, also revealed that any communication involving Thurwell and the OCG had been re-routed through Spain from a device in the UK, meaning the fourth man was definitely still among the corruption team.
Viewers were noticeable underwhelmed to learn the identity of the elusive criminal, as the series ended on an ambiguous note
It was at least revealed that the so-called fourth man was actually DSU Ian Buckells, who had been originally imprisoned after appearing to have been framed by Davidson
The team from AC-12 found a strong box hidden under the floor of the O CG's workshop during the nail-biting episode
DI Arnott was finally called in for a meeting with Occupational Health, who noted that while he hadn't broken the law through his excessive painkiller use, he should take time off from his duties
After being imprisoned for her own corrupt behaviour, police officer Jo Davidson was taken away in a police van by corrupt prison guards under the ruse that she was being interviewed at Hillside Lane.
However after it was became clear that 'H' was involved in the officer being taken away, AC-12 retraced the van just in time to rescue Davidson, and vowed to get her into witness protection if she came clean on H's identity.
Davidson was reluctant to give up the man in charge of the Order who kept her hostage for so many years, and so AC-12 opted to return their investigation to former Chief Superintendent Patrick Fairbank- the corrupt officer who was previously jailed for his connections to abuse in the Sands View Boys Home.
However once again Fairbank, claimed he 'did not remember' anything related to Davidson or the OCG, leaving a clearly-frustrated Hastings storming out of the interview.
Proving to be the clue that would crack open this decade-long mystery, Bishop spotted the same 'definately' spelling inside a written note found in the records related to Lawrence Christopher's murder.
The case was being investigated by Vella before she was murdered, having learned that the botched work corrupt police officers meant no one was ever charged with the racially-charged crime.
As AC-12 debated whether to go public with the information, Hastings finally confessed to Fleming and Arnott about the mystery bag of money he gave to John Corbett's widow Steph, admitting he gave her the cash as a kind-hearted gesture.
Despite finally uncovering the identity of H through a long paper trail of corrupt officers, fans were surprised to learn the organisation's powers had been significantly weakened
As the final shot of the AC-12 elevator showed the trio reunited as they travelled down the lift together, viewers were less hopeful on whether they'll get to see them together again in a seventh series
She's become one of the show's most maligned characters, but viewers were left hoping that detective Carmichael had some glimmer of compassion after Hastings decided to make a confession
Line of Duty fans have previously speculated that Philip Osborne (centre) was 'H, according to a poll by YouGov
Clearly still a lawful man despite years working in corruption, Hastings admitted that he did reveal that John Corbett was working undercover in organised crime, indirectly leading to his death
He also fiercely denied revealing Corbett's identity as an Undercover Officer to the OCG, which eventually lead to his death.
Regardless, the written note finally set the stage for the most important police interview in the show's history, with the stage set at last for Hastings to confront the criminal H who had caused so much havoc in AC-12.
The episode concluded on an uncertain note, with Hastings coming clean about revealing Corbett's status as an UCO after vowing to appeal his forced retirement.
As he left with the AC-12 team, an on-screen text noted that the unit's powers to curb wrongdoing in the force had 'never been weaker'.
Elsewhere Davidson was seen entering Witness Protection, while it appeared that if Buckells gained immunity, none of the evidence for corruption would be heard in court, meaning the entire investigation would have been for nothing.
Anticipated: Given the show's record-breaking viewership, fans hoped that the finale would answer all their burning questions, including the identity of the elusive 'H
Ahead of the sixth series finale, feared by many to be the show's last hurrah, fans got a glimpse of the episode through an action-packed trailer, complete with a police standoff, the return of balaclava men and the discovery of a written note with the 'definately' misspelling.
However, despite the huge success of the BBC show, actor Martin Compston revealed the BBC drama could be coming to an end.
Compston - who previously revealed that executive decisions about the series are 'above his pay grade' - cast doubt on the show's future during an appearance on The Jonathan Ross Show.
Speaking on Saturday's show, the actor said: 'We won't come back just for the sake of it. That's for sure. We'll come back if there's