A/N from McStaken: Welcome to my nightmare! No, literally this started out as a nightmare (Thank you Arkham Knight Scarecrow) and then it became…. This. Shameless self-insert. Shameless. With a twist. I feel sorry for Sarah Booth because we tend to abuse our precious characters. Like a lot. So welcome to Patient Zero - a love letter of awfulness to Jonathan Crane. Thanks for the nightmares, spooky. Happy Halloween.

A/N from L.D.: So McStaken actually wrote most/all of this and I helped edit it. Normal people would think to post it on McStaken's account, buuut normal people also have self control and the ability to update on a schedule and not update because they're so many chapters ahead and just really *really* want to share it with people. *eyes McStaken*. So that's why it's being posted on my account. Especially because she likes to sneak post while I'm sleeping or while I'm working because time zone differences and I can't help control her impulses. So I hope you enjoy, and don't worry, all reviews will be forwarded to McStaken so if you have any specific questions, they will definitely be answered. Enjoy and have a Happy Halloween! Hopefully yours is gonna go better than our main character's.

Chapter 1

Gotham. Autumn.

Gotham's weather was unpredictable at best. There was no standard adjustment period between summer and autumn. It would be pleasantly warm one day and then a cold snap would drop the city's temperatures into almost winter conditions the next. With the cold snap came winter's first bite - flu. This year's wasn't just any old flu, it was nasty and virulent - had struck at least 75% of the city's citizenry already. Elderly people were dying from the assault on their bodies and the city's news was gripped with the Great Flu Epidemic statistics and predictions. Anchors talked about doctors and the medical system being under strain from the needless appointments - sufferers were advised to rest and avoid contact with anyone who had long term medical problems or were elderly. Those as yet unaffected by the epidemic were urged - get your flu-jab now.

Sarah Booth. Age 25. 149 Rosemount Ave. West Gotham. Hair brown, eyes brown. Five foot six, 125 pounds soaking wet, and - here for her flu-jab. She worked in retail - had seen a lot of sick people and a lot of sick co-workers. This year's flu had, thankfully, passed her by for now - but she wasn't about to coast on that luck. She couldn't afford to take time off work because Bill or Susan had given her their germs.

The pharmacy she'd chosen on her lunch-break looked eerily deserted. One of those old mom-and-pop pharmacies with wooden shelves and dank, dark aisles of products. The cough and cold aisle - she noticed - had been ransacked. No Lemsip on display, no cough drops. It was barren and empty - like the rest of the store. Well, not quite empty. The pharmacist was still here.

He appeared out of one of the offices like a wraith - skinny as a rake but with a head of unruly brown hair and wire-rimmed glasses. 'Finished with your forms?' His voice was lilting - definitely not born and bred Gothamite, there was still a little southern accent in it - but she liked it. It was a calming voice.

'Yes.' She handed the forms back and glanced around uneasily in the silence. There wasn't even a cashier standing by the till. 'Where is everyone?'

'Hm, struck down by that flu or on their lunch-break.' The pharmacist dismissed easily. 'But I'm still here. We can do this now, if you want, or we can make an appointment.' He added archly.

'Now - if you have time.' She fidgeted nervously. No time to prepare for the needle - Sarah did not particularly like needles - or what came after. The blood.

The pharmacist glanced around them and smiled strangely. 'I think we have time. Follow me.'

He took the forms with him into a partitioned section of the store and pointed her to the seat closest to the desk as he scanned the forms. 'Before we begin -' His glasses flashed as he glanced up at her. 'I have to ask, are you allergic to anything? Eggs, shellfish, peanuts?'

'No,' she replied and watched him pull a notebook towards him to scribble her answer into it. Was this standard practice?

'Your medical history is sparing.' He noted. 'Though I don't see any major problems - I must tell you, Ms Booth that we're trialling a new drug this winter. The side effects can… vary. I'd like you to tell me whatever you feel after the needle.'

Needle. She nodded and he scribbled something down into his pad before he reached into a desk drawer and - She'd expected a small and none too intimidating needle. This was not small. It was filled with a watery yellow substance. Sarah was sure she'd gone white at the sight of it. He noticed her discomfort and chuckled. 'Not a fan of getting shots?'

'N-no.' She answered and looked away - anywhere but at the needle.

He seemed amused by her reluctance. 'Don't worry - everyone hates taking their medicine. It's just a little prick. We'll do it on three.' He promised. 'One-'

She'd expected the needle at two but she felt the pain just after he'd finished saying one. She felt it slide into her vein and - for some reason - the jab felt cold.

'Now,' He said as the metal slid out. 'What do you see?'

She looked at him confused for a second and then down at her arm. It was coated in blood. Blood trickled steadily from the injection site and down her arm - it dripped off her fingers and she gave a ragged gasp of surprise. It did not go unnoticed by the pharmacist.

'What?' He demanded. 'What are you seeing?!'

She tried to wipe the blood away, gripped her shoulder with her good arm to stem the bleeding but it seeped through her fingers relentlessly. She could feel the hysteria building. 'I'm bleeding - it won't stop bleeding! There's so much blood!' She gasped. Could taste the metal in the air as blood pooled in her lap and it still kept bleeding. 'Help me!' She begged.

The pharmacist was unmoved by her plea as he scribbled in the notepad again. 'Heamophobia. Interesting.'

'You need to-' She looked back down at her arm - it was fine. No metallic taste in the air - no blood on her fingers or her clothes. Her arm looked fine. 'What? Where did-?'

His head snapped up at her confusion, his glasses flashed alarmingly. 'What is it?'

There was nothing there but the raised welt where she'd taken the needle. 'I -' She blinked. 'I was bleeding, and now I'm not - it doesn't look like I ever was. What was in that flu-jab?!' She demanded.

'What?!' He snapped - he seemed angry now. 'I gave you a full dose-'

There was a crash from the back of the store. A door being kicked in. A dark and angrier voice yelled 'CRANE!' and it was getting closer.

Sarah's head snapped to the pharmacist as he pulled a burlap mask from his pocket and - oh god it was Scarecrow. She hadn't realised until she'd seen the mask but the man in the white labcoat - it was Scarecrow. He'd escaped from Arkham weeks ago. There had been a manhunt for him ever since.

'Why doesn't my serum work on you?' He turned and demanded under that terrifying mask. He was reaching out to grab her - oh god she didn't want to die screaming! - as he snarled 'How do you have immunity? Tell me!'

'I - I don't-' She spluttered. The door broke under a forceful boot, a Batarang snapped against his outstretched hand and Crane backed away from her as she ducked and cringed away from the blur that ran through the door and straight for the other man.

There was a click and a hiss as they tussled and then - two hands grabbed her and hauled her up - she screamed, thinking it was Scarecrow but as the dust and mayhem and Fear Toxin settled she realised it was Batman.

Scarecrow was gone.