Hey everyone! This is my first attempt at fan fiction so please be kind. All constructive criticism graciously accepted so please r & r.

Since this is the final season I got a bit nostalgic and decided to write a "what could have been" story about two of my all time favourite characters. Hope you enjoy it.

Disclaimer: I do not own the characters or the programme, it is just a bit of wishful thinking.

Rating: K, just to be on the safe side.

Title: What Could Have Been.

Summary: A face from the past re-awakens old feelings that Mark thought he had buried long ago.

She stood across the street quietly watching as ambulances pulled up, unloading patients onto eager residents and their med students and then stared as they sped away to pick up the next unfortunate soul who needed their assistance. As she stood there staring she silently mulled over her decision to return. Was she glad she was back? She didn't know. Was it going to work out this time? She wasn't sure. Would everything have changed since she left? More than likely. Would he still be there? She hoped so. Did she still love him? Of course she did. Was this where she belonged? Definitely.

She took a deep breath, inhaling the crisp autumn air and smiled. She was home again.

She slowly walked across the street towards the sliding doors she had entered hundreds of times. As the hustle and bustle of the busy ER enveloped her any doubts she still had evaporated instantly.

She approached the admit desk cautiously. The unfamiliar clerk looked at her impatiently.

"Can I help you?" He asked in a brusque manner.

"Can you tell me where I can find Dr Greene?" She asked.

"If you want to see a doctor you are gonna have to take a number and wait in line like everyone else" He answered in an exasperated tone as he turned away from her to answer the phone.

Her eyes began scanning her surroundings in the hope that he would appear from somewhere. Just as she was about to turn to go in search of him she caught sight of him backing out of exam 3 closely studying a patient's chart. Unconsciously, she held her breath as he slowly turned in her direction. Then almost as if he had sensed her presence he looked up from the chart and stared right into her eyes as his mouth fell open slightly.

He looked exactly as she remembered him the last time she saw him. Her stomach fluttered at the sight of him. The slightly shocked expression on his face and the flicker of amazement in his eyes warmed her heart.

She smiled at him as he stood there speechless. He blinked as if he was trying to figure out whether the woman who stood before him was real or if she was just a figment of his imagination. As realisation dawned on him that it was in fact her, a rush of emotion swept over him. All the feelings that he believed he had buried so long ago instantly invaded his brain.

He carefully stepped towards her, afraid that if he advanced too quickly she would disappear. As he got closer his steps quickened, as did his heartbeat. He had almost forgotten the effect she had on him. Those eyes, that smile, so many memories came rushing back to him. It was as if the time in his life that she had been a part of was flashing before his eyes.

As he finally reached her the last memory to pass through his mind was the kiss, the one perfect kiss that they had shared so long ago. The sweetest, softest, most passionate kiss of his whole entire life.

Without saying a word he automatically put his arms around her and pulled her close to him, afraid to let go in case she left him again.

She gladly accepted his close embrace and silently heaved a sigh of relief that there was no tension caused by the way that she had left him. She almost been afraid of what his reaction to her return would be.

As they reluctantly parted they looked deep into each other's eyes and it was like time had stopped. They were only conscious of each other; the hectic ER had faded into the background.

"You have no idea how good it is to see you." He said with a huge grin on his face.

"I have missed you so much" She replied slowly, her eyes never leaving his.

"I missed you too Susan"