Contains spoilers for episode 7 of The Missing series 2

The Missing series two has featured as many twists and turns as a German rollercoaster, and as it careers towards its conclusion tonight there are bound to be several more to come.

There are still numerous questions we want answered. Why did Sophie lay flowers on Henry Reed's grave? What exactly did Brigadier Stone do to make her despise him so much? Who was the enigmatic Arab man following Julien Baptiste? Was he ever real? What happened to the older Bazani sister in Iraq? And how did Adam Gettrick buy a toy monkey without any cash (possibly using a credit card that will later be used to trace his whereabouts)?

But judging by Twitter, Facebook and our comments section, there's one question in particular that has been giving viewers sleepless nights: who is the body in the shed?

The results of genetic tests carried out by the British Army on the charred remains found in the Websters' back garden suggest they belong to their abducted daughter Alice. We’re told comparisons with the DNA of her dad Sam show they are related.

The fact that the girl who claimed to be Alice is still alive doesn’t affect that, because we’re almost certain she is actually fellow abductee Sophie Giroux (her captor Adam Gettrick calls her Sophie, she speaks to him in Sophie’s mother tongue, French, and neither Alice’s mum nor former detective believe this girl is Alice).

So up to last week, the idea was that the real Alice really was the one found dead in the shed fire. But then we reached the end of episode seven and... locked inside a dingy store room in the remote Alpine cabin Gettrick and Sophie are now living in, we get a brief glimpse of a girl he calls Alice.

We only see her for a moment, but she immediately looks more like the 13-year-old Alice Webster we met at the start of the series. So now the question is: who is that in the shed?

The answer many viewers seem to be leaning towards is that it's Lena Garber, another abducted girl who was spotted riding a rollercoaster with Sophie and Alice during a rare day out of their shared prison.

In that case, it means the DNA evidence has been faked, which is at least feasible since Gettrick works at the Army barracks and so do several other characters who we suspect are wrapped up in this dirty web of lies.

Lena must therefore have died, or been killed, while living with Gettrick, Sophie and Alice, and her body used to fake fake Alice’s death (or even worse, she had been alive when she was locked in the shed by Gettrick, a sacrifice for Alice).

It’s a good theory and may well turn out to be the right one, but I have another idea to throw into the mix and – sorry – but it involves yet another captive girl...

Let’s assume for a minute that the results of the DNA test on the body in the shed are genuine. After all, unless we’re talking about a mass conspiracy, getting into an Army lab and tampering with the evidence would not only be extremely risky, it would also involve some level of forensics knowledge (although a sample of Alice Webster's DNA would at least be easy for Gettrick to get his hands on). 

So how else could the body in the shed have Webster DNA? For me, the theory that Alice's dad Sam Webster was somehow also Lena's father is a bit too far-fetched. But what if the body in the shed was...

...Alice’s daughter.

Remember, Alice was abducted 13 years before her supposed return. We don’t know her age at the time for sure but she looked to be close to her early teens.

We also know Gettrick has fathered at least one other child with the abductees: Lucy, who is supposedly Sophie’s daughter.

What if the real Alice gave birth soon after she was taken? By the time she returned, she’d be mother to a teenager. And what if that child died and was placed in the Webster’s shed before it was set on fire? That would mean an adult-sized body with DNA shared with Alice’s father.

In fact, could Gettrick's decision to let Sophie return as Alice have been sparked in the first place by the death of Alice's daughter, which gave him the perfect opportunity to fake Alice's death and end the search for her once and for all?

He couldn't send the real Alice home, of course, because he couldn't trust her not to turn him in. We've seen that she still needs to be locked away (we even heard that she was transported to the Alps in the car boot). After all these years, she is clearly not quite ready to fully give into him.

Whether or not my theory about the body in the shed is right, let's hope that last part is at least true, and that Alice has enough fight left in her to give tonight's series finale a positive ending. After the ordeal The Missing has put us through over the last eight weeks, god knows we deserve it.

The finale of The Missing series two is tonight, Wednesday 30th November, at 9pm on BBC1