Abi seems too obvious atm tbh
I have a theory about Lucy's killer. I think it may be Abby and Max is in on it (he could be helping her cover it up).
I really feel Abby has acted shady around Emma since day 1. She was also the one who sent Max the photos of him and Lucy.
She seemed like she could care less what happened to Emma when Max took her to the hospital.
And also on their way to the hospital, Emma said she knew Lauren was not the killer and when Max acted confused she said 'you know'.
Another thing I noted was that Emma had the killer's number on her phone. She must have known the killer personally and the way she spoke to the killer made it seem like they knew each other.
And like others have noted, Emma didn't go to the police straight away which suggests she may have been close to the killer.
That Irish dude in the police force or aleks, he is capable of a lot. I jest, I believe it is Abi- she was very shaky around April time and the reason why she failed her exams was because she couldn't think about revision, only what she had done- a hopeful vet med student doesn't just fail like that. Also the way she drowned Lauren on Halloween suggests she has a temper and the strength to kill a grown woman in the heat of the moment. She also has a clear motive in that Lucy was sleeping with her dad, and after the whole Stacey Christmas 2009 affair, Lucy was the straw that broke the camels back
Patrick did it. He's faking his illness to throw people off.
Seriously though, I think it was Abby Branning.
I can't believe how foolish you people are, it was clearly that psycho Tracy...
If Lauren did it, then she wouldn't have been so cosy with Peter without cracking under the pressure right? (I don't know if they're still together, but they were at some point post Lucy's death).
Max. She wanted to stop sleeping with him. NO ONE ESCAPES THAT BRANNING ****!