Line of Duty series six has another acronym for you to learn (but it’s not the rude word you thought it was)

If UK police drama Line of Duty has shown us anything over the years, besides the fact that Adrian Dunbar’s glare could wither an oak tree, it’s that entertainment can be educational too.

Amid the high-octane scenes of crime and corruption, the BBC One series has never shied away from subjecting its viewers to a whole host of police acronyms and abbreviations.

Whether this be the name of Ted Hastings’ fictional anti-corruption unit AC-12, or its frequent references to OCGs and AFOs (if you haven’t picked these up by now, we can’t help you), the series is packed to the brim with immersive – albeit sometimes mildly confusing – details such as these.

And it appears that the show’s writer Jed Mercurio sees no reason to alter course with season six, which debuted on Sunday at 9pm.

The new season came equipped with yet another acronym for you to learn.

Those tuning in on Sunday soon found themselves having to get their head around the acronym, “CHIS”, as detectives delved into another murder mystery.

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The real-life acronym stands for “covert human intelligence source” – or, in layman’s terms, an informant.

The BBC voiceover even clarified what the term meant as the show ended. But, without any explanation given by the characters, viewers flocked to Twitter to ask what it meant.

Presenter Richard Osman wondered if it was a clue to the identity of H - the apparently one remaining corrupt police officer that Ted and co are trying to track down.

Others viewers misheard the acronym and the term, errr, “jizz” started trending on Twitter.

Some helpful fans just took it as an opportunity to explain all the other terms that have become part of any LOD aficionados’ lingo and might well come in handy over the next five weeks.

And others didn’t really understand what any of it meant, but had a jolly good time watching it anyway.

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