This screen shot is the actually point of shooting - directly into the back of Stevie's head and her hair blows upwards
So putting together River's recollection of that night and information from the detective team:
River: We talk. She crosses the road, she stops halfway. She turns her head. There's a look of recognition.
DCI Chrissie Read: Too right, there was a look of recognition. She'd been in that car. You must have talked about something. (Episode 1 confirmed Stevie's DNA was on 'Riley's car' - but we now know it was INSIDE THE CAR)
River: We talked about nothing. We worked - and then we had lunch, and then, we worked some more. We went for a Chinese. (He appears to have no memory about what they discussed)
[Chrissie Read then introduces more information about Stevie's family background. (a) drug dealers who used to run half of East London (b) her family alibied for the night of the shooting (c) Stevie sent her own brother down - an ultimate betrayal.
River is going to the wake - so Read asks that he watches out for anything.
I don't know if it is significant so I will just record that Stevie's wake was held in 'Murphies' bar .]
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Jimmy (Stevie's brother is serving being the bar)
River: Hello, Jimmy.
Jimmy: So, you got him? What was he -- some smacked-out kid, looking to have a pop at a cop?
Why did it have to be my sister?
There was a time I could have put a gun to somebody's head and found him myself.
Now, I'm a reformed man.
River: You've been gone a long time.
Jimmy: Old sins cast long shadows.
River: Everyone deserves a second chance.
Jimmy: I decapitated a man, River.
River: I know.
Jimmy: Watch your back tonight.
I have posted a screencap of Jimmy with tattoo on right-hand side of his neck
(That's it - I have run out my 6 photos in 24 hours on Mumsnet!)