If you were worried the Line Of Duty finale might leave things up in the air, rest assured that answers are “definitely” coming. 

The BBC has released a new trailer for the final episode, which suggests the identity of ‘the fourth man’ – otherwise known as ‘H’ – will be revealed. 

The 30 second clip teases that “every investigation has led to this”, as it lines up key suspects DCS Patrica Carmichael, Chief Constable Philip Osborne, Superintendent Ted Hastings, DI Kate Fleming and ex-officer Marcus Thurwell. 

It also previews other dramatic events in store, including another armed face-off AC-12 have with members of the OCG as they look to secure the suspect. 

DCI Jo Davidson also faces an uncertain future, following her imprisonment in Sunday’s episode. 

The former MIT boss – who was revealed to be in league with organised crime due to her family connection to Tommy Hunter – is seen being transferred in a van with a corrupt prison officer, suggesting she could await the same fate as her birth father. Hunter was killed in series two after bent officers staged an ambush on his police convoy to stop him revealing their identities as he entered witness protection. 

There is also another ominous misspelling of the word “definite”, which has been a known trait of ‘H’, and indeed of Ted Hastings…

The internet is already flooded with theories ahead of Sunday night’s finale, as many fans believe Marcus Thurwell is actually alive, after the character was found dead at his Spanish villa – and some of then claim to have the proof. 

Suspicions have also been raised about DCS Carmichael, as some viewers spotted what they believe might be a clue that confirms she’s ‘H’. 

Line Of Duty concludes on Sunday at 9pm on BBC One.