Nearly 8 million viewers were glued to their seats as Line Of Duty returned after a two-year absence on Sunday night, but amidst all of the twists and turns, there were some details in the opening episode you might just have missed.
As the series began with AC-12 investigating the organised crime group that were revealed to be operating at the end of series four, there was a surprise planted for long-term fans of the show.
Among the balaclava-clad members of the gang was a character called Ryan Pilkington, who appeared as a child back in the very first series in 2012.
You may recall Ryan was the BMX-riding youth who was working for gangster Tommy Hunter.
He famously placed DS Steve Arnott’s fingers in a vice in an attempt to cut them off after the AC-12 officer was ambushed during a surveillance operation.
Ryan was later arrested for his his crimes, but dodged doing time by giving up information on Hunter’s criminal activities to police.
However, it seems he has learned nothing from his previous brushes with the law, as he now works with the organised crime gang, which is being led by undercover officer Steve Corbett.
Elsewhere in the episode, there was also a special little detail planted as Arnott attempted to get his romantic live back on track.
As viewers saw him chatting to a woman called Tina Watts on a dating app, some noticed she was a little familiar.
That’s because she is the real-life wife of Martin Compston, who plays DS Arnott.
Martin later joked about his wife, US actor Tianna Chanel Flynn’s, appearance on the show, also revealing the dog in her character’s online dating profile was also their real-life pet.
“Fair to say I know old Tina Watts and her dog fairly well,” he wrote.
Martin and Tianna married in 2016, in a Glaswegian ceremony attended by his fellow Line Of Duty stars, Vicky McClure and Adrian Dunbar, who play DI Kate Flemming and Superintendent Ted Hastings.
Line Of Duty continues on Sunday at 9pm on BBC One.