‘Marcella’ served up the biggest twist of the series so far on Monday (27 March) night, when it was revealed the police could be looking for a female child killer.

The ITV crime noir has focused on the hunt to find out who is responsible for the kidnap and murder of 17 children, and while it had been majoritively men who had fallen under suspicion, Marcella’s discovery of a box of tampons at the crime scene turned the investigation on its head.

As a result, viewers were left questioning which of the show’s female characters could be behind the crimes, with a wide range of interesting theories floating around on social media.

Jason’s girlfriend Rebecca put herself in the frame when it looked like she had done something to care home worker Gail, after her discovery that Joel ending up in a locked-in state was “no accident”:

Rebecca’s link to Joel was also questioned. Are they related? Why was she at the home to visit him? And is she also manipulating Edward?

Others believed children’s charity boss Maya had aroused suspicion, especially as she was seen visiting a derelict house – a potential new location to hide the children? 

Her obvious link to abused children also gives her unrivaled access to information about them and their abusers, and one fan questioned whether she could be killing them to protect them: 

It’s also worth noting that she also paid her employee Sascha to plant evidence framing her husband Vince at the scene of the murders. 

Speaking of which, Sascha’s involvement in the killings was brought into question: 

Her partner Jojo also came under suspicion, as it was pointed out a) how desperate she is for a child (even going to the lengths of sleeping with a stranger in a club to try and get pregnant) and b) she also has surgery experience as a vet, so would therefore be able to carry out the procedures on the victims: 

However, some fans believe it could be a ring of women with many of the show’s supporting female characters involved.

It was pointed out they all have in common the fact they either don’t or can’t have children: 

With two episodes of the series left, we’re still a little way off finding the real identity of the killer (or killers), and with this being ‘Marcella’, there’s bound to be a few more twists in the tale yet. 

And don’t forget, we still not sure about convicted paedophile Phil Dawkins’s involvement, and what really happened between Reg and Alan at that party all those years ago…

‘Marcella’ continues next Monday at 9pm on ITV.