This is my first Line of Duty fanfic and the first fanfic I have written in many years so a bit rusty on my writing. I hope you enjoy!

Chapter 1

It wasn't everyday when walking through her work building that Kate saw someone who looked so out of place as the girl at the front desk was. She was wearing a massive backpack which Kate only saw people climbing up mountains like Everest wearing and her outfit of a skirt, camisole and light weight short sleeve cardigan was far to summery for the September chill that hung in the air. It was pouring with rain and the girl was soaking wet because of it. Clearly she didn't bring a coat with her. Her long reddish brown curly hair was piled up on her head and her Harry Potter style glasses were splattered with so many water droplets Kate was surprised she could see anything. When the light hit her hair just right though, it looked like she had fire red hair which would catch anyone's attention without them even thinking about it.

"Um, excuse me. I'm trying to find someone but I'm not sure how to find him in this place."

"Who is it you are looking for?" the receptionist asked.

"DS Steve Arnott." Kate stopped in her tracks at Steve's name being mentioned. She turned round to face the girl.

"Hi, can I help you?" she asked. The young woman turned and smiled at Kate.

"I hope so, is Steve here?"

"I'd need to know who you are and why you want him first I'm afraid."

"I'm Lottie, his little sister. He was meant to pick me up at the train station two hours ago but never showed," she explained. It was only then that Kate noticed that Lottie sounded tired and through her drenched state was a bit unkempt but doing her best given the massive backpack.

"Sorry to ask but do you have any ID?" Instantly Lottie held out a passport she clearly had prepared in her hands on arrival. It checked out and Lottie signed the guest list for the building.

"Follow me. I'm Kate by the way." A large grin spread across Lottie's face.

"So you're Kate. I've heard a lot about you. All good I promise."

"I'm afraid I haven't heard anything about you." Lottie rolled her eyes.

"Typical Steve! Only needs to speak about what is important in the moment. Takes secrets to the grave. No wonder he became a cop."

As the two women wondered through the floors and corridors of the building, slowing down a bit whilst Lottie quickly wiped the rain off her glasses, Kate came to the conclusion that Lottie shared many of Steve's traits. However she was in ways his polar opposite. She was very open, honest (brutal at times), witty and high spirited despite being exhausted. She was warm hearted to the depths of her soul.

Finally they arrived at the AC-12 office and as expected Steve was at his desk so engrossed in his work he didn't notice Kate or Lottie enter the room or even look up from his screen.

"Steve, mate. You have a delivery." Steve, having never had anything delivered to the office before, looked up confused. His eyes quickly widened and his mouth opened in surprise seeing Lottie.

"I don't believe it," he said with a chuckle as he stood up and approached Lottie. She at the same time dropped her backpack on the floor with a heavy thud only then to be pulled into a bear hug by Steve. She giggled and then squealed when he lifted her off the ground. Seeing the siblings side by side Kate could see their similar features but Lottie was also taller than Steve by a couple of inches and was thinner in frame.

"What are you doing here? You aren't due until tomorrow" he asked as they parted.

"You're kidding right?"

"No, you said your flight was on the evening of 4th September."

"Yes, from Australia. You ever heard of a thing called the International Date Line?" Realizing his mistake, what the current time was and the weather he closed his eyes and let out a frustrated sigh.

"Shit, I'm so sorry. Does being really busy with work sound like a good enough excuse for being a shit brother?"

"I'll let it pass if you do something for me?"

"What?" She then held out a hand towards him.

"Flat key, address, alarm code, credit card and cash." He raised his eyebrows. "I've not slept since Australia. I've not eaten since Singapore and desperate for a drink after two hours on a train platform with no services waiting for you. Not to mention I am soaked to the bone thanks to my delightful walk over here. There's a café around the corner where I can get take away food and drink while I wait for a taxi which you are paying for and FYI I will keep the cash change. I will be showering and straight to bed when I get to yours and most likely will still be asleep when you get back whenever that may be. If I am awake I'm ordering a pizza, again paid for by you."

Knowing there was no way he could say no, Steve walked over to his desk to collect the various items without uttering a word.

"You have to tell me how you do that" Kate said softly.

"Lifetime of training. You'll pick it up in five minutes with a brain like yours." A nearby evidence board caught Lottie's attention. There were a variety of documents on it with lines connecting as well as surveillance of a young man going on a coffee run and an old rusty bicycle, a piece of string connecting the two together.

"Is that what you're working on?" Lottie asked pointing to the board.

"That's classified" a voice came from behind them and the two women turned to see Ted and Dot.

"Sir, this is Steve's sister, Lottie. Lottie this is Superintendant Ted Hastings and Detective Inspector Matthew Cottan." Lottie shook their hands and Steve joined the group.

"Pleasure to meet you both. Sorry for the office intrusion but my idiot of an older brother here is to blame."

"Sorry, Sir" Steve said and handed over the items to Lottie.

"It's alright on this one occasion as a brief visit," Ted replied nicely but everyone knew it was an equivalent of a clip round the ear aimed at Steve.

"Yeah, you don't want me taking all your cases from you, do you Steve? Especially ones with intriguing bicycles."

"That's still classified. Why don't you let the real police do their jobs and go do whatever young girls do," Dot addressed her with a cocky grin letting Lottie know this was his case and that confirming what Steve had said about Dot. He really was a piece of shit. Before Ted, Kate and Steve could react to his rudeness, Lottie got in first.

"No, that's fair. At least I'm not wasting my time tracking the wrong suspect." She bent down and picked up the backpack with ease, throwing it over one of her shoulders. The size and weight of it Kate thought would have sent her flying on one shoulder but Lottie was stronger than she looked.

"What makes you say that?" Dot asked putting his hands in his pockets showing he was clearly uncomfortable.

"Obvious isn't it? The bikes' break cable." All four of the AC-12 team turned to look at the board pictures.

"What about it?" Dot asked.

"Well, I am just a young girl so what the hell could I know, right? I do know though that bikes can be adapted just like cars for their drivers. The front and rear break cable has been swapped so the break is on the left not the right. The pictures of your suspect all show that he is right handed. The devil's in the detail." She let the bombshell hang in the air for a few seconds before speaking again.

"Well, I best be off. Need to get out of these wet things and get my beauty sleep and all. It was nice meeting you all at last."

"I'll show you out." Steve quickly said rubbing the back of his neck. He knew Dot was going to be a right pain in the ass to him now for the rest of the day now.

"No, no, you're busy with work remember? I'll see you when I see you at home." Kate opened the gate and Lottie winked at her as she passed through.

"By the way, you aren't a shit brother but you could do with polishing your timing!" Lottie said loudly as she headed to the door and with that she was gone.

"Well, she's ….. colourful," Ted observed with a smile. Clearly he liked her.

"You have no idea," Steve muttered. He turned and noticed Dot heading for the kitchen with an extra heavy stomp in his step.