Forgot who someone is? Confused by all the new characters? Don't worry, here's our handy who's who guide to the fifth series of Line of Duty...

A van full of seized drugs is under police protection when it’s suddenly attacked by an armed gang wearing balaclavas in the opening scenes of the new series of Line of Duty.

Soon, AC-12 are on the case for a fifth series of the BBC1 hit, which returns this Sunday at 9pm.

Here’s our who’s who guide to all the main characters in the new series of Line of Duty…

Supt Ted Hastings (Adrian Dunbar)

Line of Duty Ted

The big cheese at AC-12, Ted’s team are on the case again, asking the tough questions. But in a world where you can’t trust anyone, should we be trusting Ted?

DS Steve Arnott (Martin Compston)

Line of Duty Steve

Poor Steve almost met his maker in the last series when he was attacked and shoved down some stairs by balaclava man. Now, he wants justice… “There are some good shocks this series,” says Martin, who plays Steve.

DS Kate Fleming (Vicky McClure)

Line of Duty Kate

Kate has been a linchpin of the team and once again finds herself at the centre of a really tricky case…

John Corbett (Stephen Graham)

Line of Duty

The leader of a particularly nasty organised crime gang, who launch a violent heist to steal a large haul of drugs from a van guarded by police.

Lisa Mcqueen (Rochenda Sandall)

Line of Duty McQueen (ROCHENDA SANDALL)

She’s the only woman in John Corbett’s gang and gets caught up in an incident during the deadly raid…

PC Jane Cafferty (Sian Reese-Williams)

A mum and police officer, Jane is protecting the van when it’s held up by the violent balaclava gang.

PC Tatleen Sohota (Taj Atwal)

This young officer eagerly sets about helping AC-12 find possible clues as to who’s behind the raid on the van.

Supt Alison Powell (Susan Vidler)

Why does the police boss seem so determined to stop AC-12 investigating a top-secret undercover operation?

PCC Rohan Sindwhani (Ace Bhatti)

The police crime commissioner announces details to the press about both the raid and the police murders.

Line of Duty returns on Sunday on BBC1.