The first episode focused on the disappearance of primary school teacher Gemma Hillman.
Viewers got a glimpse of her life 36 hours before she went missing, showing one of her colleagues sexually harassing her and her boyfriend Greg threatening her.
The episode then skipped ahead, showing officers searching for Gemma, while Greg was interviewed by detectives.
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Later in the show, DC Martin Young and his surveillance partner Stella arrived to set up their surveillance post in the home of single mum Zoe and her daughter Caitlin.
They watched Greg Sullivan, who is a prime suspect in Gemma’s disappearance, as well as other residents who knew her.
However, fans all had the same question as Zoe allowed DC Young and Stella into her home without asking any questions.
Chily wrote: "Don’t show any ID going into the house though?"
Newt tweeted: "I’d be like “sorry have you got any ID?” Lol."
Chris said: "Surely you might ask for some ID?"
Lucy tweeted: "Did she even ask to see ID before she just agreed to let them use her flat to spy on someone."
Sammy added: "Would not be letting these dodgy cops into my house without ID."
And Jamal said: "Already started of strange, you let strangers into your apartment, without checking ID."
