It happened while on a case. Sherlock had taken it only because John had been insistent that they do so. Granted, if Sherlock hadn't deleted certain memories no amount of persuasion on John's part could have gotten the consulting detective to consent. But those memories were some of the first he had deleted.

A woman had come to 221B Baker Street with a tale of her abusive ex-husband and their son. She had never been able to prove her husband's abusive tendencies thanks to a crap lawyer so they had shared custody of their thirteen-year-old son. And the man had never turned on their son, in fact, their son had been quite oblivious to the whole situation so the woman hadn't fought too incredibly hard. Besides, as soon as the man had left the house, the abuse had stopped. She thought that whole messy chapter of her life was over.

But then she found out that her ex-husband was abusing her son. Considering her experience with trying to prove the man's abusive tendencies last time, she realized she needed to take a different course of action. Which is why she ended up on Sherlock and John's doorstep.

Sherlock had immediately wanted to dismiss the case. It wasn't interesting in the least, he decided. But John, ever-caring John. His heart went out to the woman and her son, and he practically demanded that Sherlock take the case. After a few minutes of shouting with the woman sitting right there, frozen in shock, Sherlock begrudgingly agreed to take the case.

Later Sherlock stubbornly deleted most of the details of the case. He would have deleted the whole damn thing, but the experience taught him there were sometimes downsides to deleting things he didn't wish to remember. He kept what he needed and kept in the dark recesses of his mind, still there enough if needed, but gone far enough that it wouldn't become a distraction. Though it did rear it's ugly head in his dreams every once and a while. But, like every other dream the consulting detective had, it was immediately deleted.

What he did keep were all the times that deleted memories tried to surface during this particular case. The first time happened when he and John had made a surprise visit to talk to the father. The door of the house was locked and, despite John's objections, Sherlock decided why not break in and take a look around. As it turned out, the door had not been locked because of the father and son's absence. Instead, John and Sherlock found themselves walking in on the father in the process of beating up the thirteen-year-old boy.

Sherlock could still see the scene with perfect clarity. The father was tall and beefy, one large hand gripping the boy's shoulder, the other raised high in the air and about to come whipping down with crushing force. The boy was tall and quite skinny and a look of terror was etched on his face. Blood and bruises covered his bare skin, angry and painful.

The father looked up the moment Sherlock and John walked in and wasted no time in fleeing. The boy fell to the floor in a heap, legs unable to hold himself steady. John yelled something at Sherlock, perhaps telling him to chase down the father, as he rushed to the boy's side, medical training taking over instinctively.

Yet Sherlock stood frozen on the spot, a wave of unfamiliar emotion rocking him to the core. The terror on the boy's face... the rage on the father's... There was something, something there in the darkest corners of Sherlock's mind trying to break out, break free. He stumbled backwards, hitting a wall, as the overwhelming emotion took over him. What was this? Sorrow? Fear? Empathy? Sherlock didn't know.

At that point Sherlock had deleted the rest of the memory until the next wave of emotion hit, but if he hadn't he would remember how John soon noticed something was wrong and all but forgot the boy on the floor for a moment. John had never seen Sherlock react to anything in any manner even close to this and it shocked and, frankly, scared him. But after a couple shakes of the head, Sherlock seemed to regain his composure and resolutely refused to explain. By then it was too late to chase down the father and John insisted they take the boy back to his mother.

Over the next couple days, Sherlock and John tried desperately to track down the father with next to no success. Sherlock refused to dwell on the incident but one night, after a particularly long and tiring day, John had already gone upstairs to bed and Sherlock settled down to try to figure out if they had missed anything. And the image of the terrified boy and enraged father flashed through his mind.

It hit Sherlock like lightning. With no wall right behind him this time, he stumbled backwards, tripped over his own feet, and landed hard on the floor. Yet he didn't notice. Flashes of other memories, memories that were supposed to be deleted, forever gone, had started running through his mind's eye.

Terror. The terror of a child. Betrayal. Bitter confusion. And pain. The pain... Sherlock shuddered violently as if the pain were real, not just a memory. And the pain wasn't just physical, he realized. There were scars inside of him from the pain, scars that no one could ever see, scars that would never go away. Scars that ensured that these memories could never be fully deleted.

Sherlock spent the rest of the night wrestling with himself as memory after memory came flooding back into full clarity. He didn't tell John the next morning, but he knew the doctor wasn't stupid enough to not notice Sherlock's bloodshot eyes and tear stained cheeks. He may have asked briefly if everything was okay but didn't push when Sherlock declined to answer.

They decided to visit the woman that day to see if there was anything she might not have told them, any clue as to where the father might have been hiding out. Neither John nor Sherlock could have foreseen what they encountered when they arrived.

As it turned out, the father realized why two strange men had shown up at his house. He realized they must have been sent there by his ex-wife. So he decided to pay her a visit. Immediately old habits resurfaced and he was hitting her. Their son, now fully aware of what had been going on before the divorce, tried to intervene. So the father turned his attention to him.

That was when John and Sherlock walked in. The mother had managed to crawl out of harm's way so John was instantly at her side. Sherlock stood frozen for a moment, waiting for the wave of memory and emotion to hit. The memories stayed quiet for the time being. The emotion, on the other hand, shifted from terror and pain to rage.

And Sherlock attacked. With an animalistic bellow, he reached for the father, hands grabbing him by the shirt collar and slamming him up against the wall. For a few horrific seconds Sherlock didn't see the tall, beefy stranger before him. Instead he saw someone poise and proper. Someone who's rage only showed through in his cold, steely eyes and his fists.

Sherlock saw his father.

Before Sherlock could do any damage, there were strong and warm hands on his arms, and a familiar soothing voice in his ear. John had left the woman's side and darted to Sherlock. Slowly, under the influence of John's coaxing, Sherlock's fingers loosened their grip on the man who had switched back to the beefy stranger. John called the police, who soon arrived and took the abusive father away, unable to deny the evidence before their very eyes. The mother and son were taken to the hospital, where they got every care they needed. She now had sole custody of her son, too. She would live in peace, never having to fear the retribution of her ex-husband ever again.

Sherlock and John went back home to Baker Street in silence. When they arrived at their flat, Sherlock went straight to his bedroom and shut the door behind him. John didn't bother trying to ask him what had happened.

From that point on, they never took another case that had any relation to abuse. Every now and again, if a case did come up with that in it, John would quickly look to Sherlock before declining the case. Sherlock's expression would always go incredibly tense yet solidly blank, relaxing only when the potential client left the flat.

John never asked. Sherlock never told. They both all but forgot the incident. And life in 221B Baker Street continued onward.

A/N: I love reviewers and live for constructive criticism.