Spoilers ahead

The new murder thriller from Harlan Coben stars Michelle Keegan as Maya, a woman who is coping with the death of her husband, Joe - but things aren't as they seem. Shock!

With the rest of the cast including Richard Armitage, Joanna Lumley, Fool Me Once is based on the Harlan Coben book of the same name.

The series synopsis reads: "Detective Sergeant Sami Kierce (Adeel Akhtar) leads the homicide investigation into Joe's death while grappling with secrets of his own.

"Meanwhile, Maya's niece and nephew, Abby and Daniel, are trying to find the truth about their mother's murder, several months earlier. Are the two cases connected?

"Fool Me Once follows these characters on a thrilling hunt for the truth that will reveal shocking secrets and change their lives forever."

Viewers have been raving about the show since it first dropped but now many have felt confused by the ending when it was revealed that [SPOILER], Maya was Joe's killer.

Many were much more convinced that the killer was Shane, Maya's friend.

If you've watched the show you'll know that his behaviour was very suspicious, especially when he tracked Maya's car and spend time standing outside of her house.

When the show came to its conclusion, it was revealed that Maya was behind Joe's death, after she discovered he had murdered her sister and was prepared to murder her too.

So why was Shane tracking Maya's car?

One person took to Reddit to write: "What was Shane’s character for? I get that he was her friend from the military but was it him that was stalking her at her house and tracking her car etc?

"Was he obsessed with her? In love with her? He was under developed and I was convinced he was dodgy as soon as he came on the screen but he turned out to be a nice guy and a loyal friend to Maya."

A second added: "Just finished Fool Me Once on @netflix, very very good series, just a few questions; what was the deal with Shane? Why was he watching Maya? Why did he put a tracker on her car? Why did he let himself in in the middle of the night?"

A third simply wrote: "Just a bit confused with Shane?"

Many have pondered that Shane's sketchy behaviour was part of the Burkett family's cover up. Others believe it was all a red herring.

Another theory is that Shane was simply being a loyal friend to Maya who, despite being very overprotective, was actually just concerned about her wellbeing.

Now, Harlan Coben himself has opened up explaining: "Spoiler: You’re military police. Your best friend suffers PTSD. She is taking medication, lying to you, lost two close family members to murders, has you test a bullet — and says she’s seeing her dead husband.

"You might want to (track) keep an eye on her and her little girl…"

Makes sense to me.

Related links:

• ‘Intense’ Netflix thriller called ’10/10′ as people hooked in first few minutes
• One of the better psychological thrillers of the last decade is streaming on Netflix
• Netflix viewers ‘never seen so many d**ks’ as in new ‘bats**t’ series