The latest season of Line Of Duty is making us want to scream. Literally.
We're only three episodes in and our heads are already spinning with all the rumours, theories and double agents as AC-12 is investigating more bent coppers.
The anti-corruption squad has turned its attentions towards Joanne Davidson, (Kelly Macdonald) the police officer heading up the murder investigation into journalist Gail Vella.
However, while newly-promoted DI Steve Arnott (Martin Compston) has his suspicions about Joanne, it appears there could be another bent copper in Operation Lighthouse.
Eagle-eyed fans spotted a sign in the background of The Hill Police Station in Sunday night's episode reading: "Please return all files once your finished using them. Thank you!"
While the wrong spelling of your (it should be you're in this context, grammar fans!) may just be an innocent mistake by production, others pointed out that it could in fact be a major clue in uncovering criminal mastermind, H.
For Line Of Duty fans not quite up to speed, season five of the BBC's crime series saw the OCG (organised crime group, keep up!) speak with H through an anonymous online messaging service.
The person identified only as H revealed themselves to be a poor speller, having written 'definately' instead of 'definitely' when communicating with the gang.
So could this sign, seen only in a throwaway scene, suggest H is a police officer working in The Hill, and part of Operation Lighthouse?
Some fans seem to think so, with one person writing on Twitter: "Who put that sign up? Grammar, spelling, clue?"
"Line Of Duty is the only show where this could be a genuine spelling error or a major clue to a bent copper who's compromising the integrity of the force for everyone else," asked a second person.
A third proposed: "This could be another clue along the lines of definately typo on the OCG instant messaging system."
Currently, Joanne herself is thought to be the hot favourite person to be H.
She's most definitely in cahoots with the OCG, with her house fortified, the hidden burner mobile and framing two of her colleagues.
She also has access to the instant messaging service favoured by the OCG, and was seen messaging someone at the end of the last episode.
Could she be H? Or does she know who H is?
There's only one way to find out...
Line of Duty continues Sundays at 9pm on BBC One.
Chosen for YouChosen for You
Most Read StoriesMost Read