Tonight's Line of Duty episode introduced us to a police officer - who isn't what he seems.
In an episode where anti-corruption unit AC-12 formally declared its investigation into Operation Lighthouse - the police probe into the death of journalist Gail Vella - we're introduced to Ryan Pilkington, the new guy in MIT.
It's apparent DI Kate Fleming, who appears to have left the anti-corruption unit, thinks she's seen him before.
She asks: "Have we worked together before?"
To which he replies: "Did you come and give a talk at the training college?"
And critics said Pilkington was embedded in an organised crime group.
TV critic Scott Bryan Tweeted: "Ryan was a kid in the OCG right back in series one. He killed Corbett (Stephen Graham) in series five, before training to be a police officer. Now he’s a police officer working on DCI Joanne Davidson’s team!!!"
One fan wrote: "Pilkington is in the house. IT’S GETTING JUICY."
Another wrote: "RYAN PILKINGTON IS THE LITTLE KID FROM THE FIRST SEASON! KATE INTERVIEWED HIM AND THAT'S HOW SHE KNOWS HIM!"
Meanwhile, AC-12 interviews Davidson as she's threatened with being arrested on suspicion of perverting the course of justice.
However, the episode hots up when Davidson's ex-partner Sergeant Farida Jatri is subsequently arrested, claiming she's been "framed" by Davidson when burner phones are found in Jatri's house.
Jatri says: "I am being framed, it's Jo - she planted those phones.
"She did not have to break-in (to Jatri's house) - she lived with me. She moved out."
And as the episode draws to a close, it is Pilkington who picks up Davidson outside the police station.
Pilkington then asks Davidson if she's heard about Jatri.
And Davidson says: "That is what happens to a rat."
Then a mysterious man with a van appears to leave a burner phone for Davidson, who collects this and starts crying.
But before all this drama happens, DI Fleming's relationship with Davidson takes another turn after their affectionate moment in the previous episode.
Kate tells Davidson her husband Mark - whose marriage is clearly in dire straits - is looking after their son Josh this weekend.
"It's Mark's turn to have Josh this weekend, if you are at a loose end?"
Davidson replies: "My diary's empty, I have just come out of a long-term relationship.
"It will be nice to see you at the weekend."
