Derek's Secret Luna: A Pregnancy, Deadpool, Jealous Ex & Dangerous Fate
๐บ๐ TEEN WOLF SEASON 4: THE Secret LUNA ๐๐บ
๐ค STORY PREMISE
Fiona McCain is eighteen years old, Stiles Stilinski's younger baby cousin, and completely human.
At least... that's what everyone thinks.
What nobody knows is that Fiona is Derek Hale's Lunaโhis fated mate.
Not even Fiona.
Not even Derek.
Well... not fully.
Derek knows she's his mate.
His wolf knows.
But Derek refuses to accept it.
Because mates are weaknesses.
Because everyone Derek has ever loved has suffered.
And because Fiona McCain is the kind of girl monsters notice.
The kind they obsess over.
The kind they hunt.
The kind they destroy.
So Derek does the only thing he thinks will keep her alive.
He pushes her away.
Hard.
Every glare.
Every cruel remark.
Every cold shoulder.
Every moment of indifference.
It's all a lie.
A desperate attempt to keep Fiona away from the danger surrounding him.
Unfortunately...
His wolf absolutely refuses to cooperate.
๐บ DEREK'S PROBLEM
Derek Hale has spent years controlling the beast inside him.
The anger.
The rage.
The possessiveness.
The instincts.
Then Fiona happened.
And everything went straight to hell.
The wolf wants:
To claim her.
To protect her.
To scent her.
To keep her beside him.
To eliminate every threat around her.
Including anyone who looks at her wrong.
Including Scott.
Including Liam.
Including Parrish.
Including half of Beacon Hills.
Derek fights those instincts every second of every day.
Sometimes he wins.
Most of the time he doesn't.
๐บ๐ THE ONE NIGHT STAND
Months ago, before Paige returned to Beacon Hills...
Derek and Fiona made a terrible mistake.
Or at least that's what Derek tells himself.
One night.
One moment of weakness.
One night where Derek forgot to be careful.
Forgot to keep his distance.
Forgot that she was his mate.
Forgot that she looked at him like he wasn't broken.
Then it happened.
And afterward Derek became even colder.
Even harsher.
Even more distant.
Fiona never understood why.
She thought Derek regretted her.
Thought he was ashamed.
Thought he hated her.
So she quietly buried her feelings and tried to move on.
๐ถ๐บ THE SECRET
Fiona is pregnant.
Neither Fiona nor Derek knows yet.
But Derek's wolf does.
The wolf can hear it.
Smell it.
Sense it.
A tiny heartbeat.
Tiny.
Fragile.
His daughter.
Every time Fiona walks into a room Derek feels strangely calmer.
Stronger.
Protective.
The wolf becomes nearly impossible to control.
Because deep down the wolf knows.
His mate is carrying his pup.
๐น๐บ PAIGE KRASIKEVA
Background
Paige was Derek's first love.
When Derek was fifteen, Ennis bit Paige hoping to turn her into a werewolf.
The transformation failed.
In canon she died after Derek mercy-killed her.
But...
She survived.
Barely.
She disappeared from Beacon Hills for years.
Everyone believed she was dead.
Including Derek.
Now she's back.
Twenty-five years old.
Beautiful.
Soft-spoken.
Sweet.
Everything Derek remembers.
Or so he thinks.
Derek has spent nearly a decade grieving Paige.
Loving Paige.
Blaming himself for Paige.
So when she returns...
He falls immediately.
Because part of him never stopped loving her.
๐นโ ๏ธ THE REAL PAIGE
Paige despises Fiona.
Not because Fiona has done anything wrong.
But because Fiona has something Paige never will.
The wolf's devotion.
Paige notices it immediately.
The way Derek watches Fiona.
The way his eyes track her.
The way he loses control around her.
The way his wolf reacts.
Paige realizes something terrifying.
Derek may love Paige.
But his wolf belongs to Fiona.
And that makes Fiona dangerous.
๐ PAIGE'S MANIPULATION
Paige never insults Fiona directly.
That would be too obvious.
Instead she smiles.
Acts supportive.
Acts concerned.
Acts sweet.
Examples
๐น Oh Fiona, that's such a brave outfit. I could never wear something like that. Then again, I've always preferred being modest.
๐น You're so lucky Derek tolerates your personality. Most people would find you exhausting.
๐น Maybe if you tried being quieter, people would take you more seriously.
๐น Derek always says he likes mature women.
๐น You're adorable, Fiona. Like a little sister.
๐น I just worry about you. You're so trusting. One day someone might take advantage of that.
Every sentence sounds innocent.
Concerned.
Helpful.
But every word is poison.
And Fiona believes all of it.
Because Paige is nice.
Paige is beautiful.
Paige is Derek's girlfriend.
So clearly Paige must know Derek better than she does.
Right?
--
๐ FIONA'S MISUNDERSTANDING
Fiona becomes convinced Derek hates her.
Why else would he always be angry around her?
Why else would he constantly avoid her?
Why else would he date someone like Paige?
Paige is everything Fiona isn't.
Elegant.
Graceful.
Confident.
Perfect.
At least that's how Fiona sees it.
She doesn't realize Derek's coldness has nothing to do with hatred.
It's fear.
Pure fear.
Because every instinct in his body screams that Fiona belongs beside him.
And Derek is terrified of what happens if he gives in.
โ ๏ธ THE DEADPOOL
Then Peter discovers something horrifying.
Fiona McCain is on the Deadpool.
Not only that.
She's near the very top.
One of the highest bounties in Beacon Hills.
Nobody understands why.
She's human.
Normal.
Harmless.
So why is someone willing to pay so much money to kill her?
The answer terrifies Derek.
Because supernatural creatures keep becoming obsessed with Fiona.
Drawn to her.
Fixated on her.
Hostile toward her.
Almost like they instinctively recognize something.
Something special.
Something valuable.
Something connected to an Alpha's bloodline.
๐บ๐ฅ WHEN DEREK LOSES CONTROL
The more danger Fiona faces...
The worse Derek becomes.
His eyes flash red more often.
His claws emerge without warning.
His growls become harder to suppress.
His wolf becomes increasingly violent.
One hunter threatens Fiona.
Derek puts him through a wall.
Another touches her arm.
Derek nearly rips his throat out.
Scott starts noticing.
Everyone starts noticing.
Derek Hale is losing control.
And nobody understands why.
Except the wolf.
The wolf knows exactly why.
His mate is in danger.
His unborn daughter is in danger.
And predators don't survive for very long around a Hale protecting his family.
๐บ๐ MAIN TROPES
๐ค Trope ๐บ Description
Fated Mates Derek and Fiona are destined mates Secret Pregnancy Fiona unknowingly carries Derek's daughter Protective Beast Derek's wolf is obsessed with protecting Fiona Miscommunication Fiona believes Derek hates her Love Triangle Fiona, Derek, and Paige Manipulative Girlfriend Paige hides cruelty behind sweetness One Night Stand Derek and Fiona's secret past Deadpool Target Fiona is one of Beacon Hills' biggest targets Jealous Rival Paige wants Fiona gone Hidden Child Derek doesn't know he's going to be a father Monster Protector Derek becomes increasingly dangerous protecting Fiona Everyone Can See It Except Them Everyone notices Derek's feelings before Fiona does
๐บ๐ And the most dangerous secret of all?
Derek Hale still doesn't know Fiona is carrying his daughter...
But his wolf already loves her. ๐ค๐บ๐ถ๐
Start Scene
Release Date 2026.06.20 / Last Updated 2026.06.20