The taxi was already speeding on its way when John's mobile signalled an incoming call.

"Greg?" John's voice sounded wary.

Sherlock's sharp ears picked up the voice of Lestrade, uncharacteristically hoarse and anxious. "John, I need you to come to Mary's clinic. Now."

"I'm actually on my way there. She sent me a text. We thought they might be involved in a robbery?" John replied, his own tone deep with concern.

"Yeah, well, it's gone beyond simple robbery, John. The perpetrator has left the scene in a stolen vehicle. And he has a hostage." Lestrade's anger was palpable, resonating through the taxi like a sudden thunderclap. Sherlock felt a surge of dread rush through him.

"Mary?" John whispered, almost too horrified to speak.

"She was completely unhurt when they took her," Lestrade assured him, but John did not look assured. "We have officers following at a distance. They'll let her go. We'll find her. It'll be okay, John." The shaking of Lestrade's voice belied the encouragement of his words.

Sherlock sat, stunned, watching his friend holding the now silent phone to his ear, forgotten. John was staring without seeing out the windscreen of the taxi, breathing hard as if he'd just run a marathon. He longed to say something comforting to John, but he was himself feeling as if all the air had gone out of the world; he had no ability to speak.

Suddenly he mobilized himself to action. He snatched up his own mobile and called an all-too-familiar number. "Mycroft," he snapped, when his brother answered. "Mary's clinic. She's been taken hostage. NSY is following, but you need to take care of this. It's MARY!"

Mycroft did not hesitate. "I'll get my best people on it," he agreed immediately, as Sherlock had known he would. Mycroft had been as impressed with Mary as Sherlock was. Mary was family.

The taxi pulled up to the clinic, now barricaded as a crime scene, and John flew out almost before the vehicle could roll to a stop. Sherlock followed a mere step behind. Doctors, nurses, and various patients stood about on the pavement or slumped in chairs just inside the building, some shell-shocked and silent, some weeping uncontrollably. Lestrade was at the door to meet them, his eyes filled with concern and a carefully controlled fury, and he ushered them inside.

"He was after drugs, of course," he began without preamble. "When he got what he wanted, he grabbed a kid for a hostage—put a gun to a child's head. Mary begged him to take her instead." Lestrade glared around at the other robbery victims with little sympathy. "She was apparently the only one who spoke up. We arrived on the scene just moments after he left with her. He had the car and driver waiting. We had our best people following the car, but they didn't dare approach openly, in case they were spotted. And, just as you pulled up, I got the report: we've lost them."

John went white. Sherlock felt staggered, but put his hand on his friend's shoulder supportively. "Mycroft's people will find her, John," he said with more confidence than he felt. He wondered how John was still standing. He wondered at the gnawing feeling his stomach, a dread he'd really never experienced before.

One of the doctors chose that moment to speak up. "You're her husband, aren't you? Dr Watson's husband?"

John turned towards him slowly. Sherlock saw the look on his friend's face and wondered if he should warn this colleague of Mary's. He chose not to.

The doctor babbled on. "You should be proud of your wife. That was the most incredible display of bravery I've ever. . . ."

And then he was out cold on the floor.

John rubbed his fist grimly and glared around at the rest of the staff, infuriated. "You let her go, without a word! Not one of you could stand up for her? Not one of you had the guts she did, to stand up for a child? She's worked here with you for how long, and you could let her stand up to a madman, alone?" Sherlock had never seen John look as dangerous as he did at that moment. He wondered if he should try to stop John, should his friend decide to go on hitting these cowardly, useless people. Or if he should join him. He was feeling as dangerous as John looked.

Lestrade put a restraining hand on John's shoulder. "Come on, mate, let's go outside, shall we?" he carefully propelled the enraged soldier towards the door. Sherlock followed protectively behind. His mind was whirling, desperate to come up with an idea that would help. He was unaccustomed to feeling so utterly useless.

John strode away from the crowd and stood a little distance away, his head up and alert, his feet wide apart. He was ready for action, if only a course of action would present itself to him. Lestrade turned to Sherlock.

"He took her switchblade. The one you gave her. She's unarmed." He scrubbed his face with his hand wearily. "You were already on your way here?"

"Mary had sent John a text. It just said, 'Love you John.' We knew something terrible was happening and came at once. We thought a robbery was the most likely scenario."

Lestrade shook his head. "Obviously, she didn't have the time to send a more detailed message. But, how did you know something terrible was happening from a text like that?"

Sherlock looked perplexed at Lestrade's ignorance. "Mary never calls John 'John', unless she's upset."

Lestrade kept careful watch over John as he nodded, enlightened. "She calls him 'Captain', doesn't she? I always wondered about that."

"It's from a poem she likes. 'Invictus', by Henley. She changed the words to it, to suit herself, she told me once, although she didn't specify in what way. I looked it up. I can guess at what she changed. Very sentimental."

Lestrade's radio broke the silence that followed, and he exploded into action once more, shouting orders into the radio and to the officers that remained on the scene, ordering John and Sherlock to stay put, then leaping into his own vehicle and speeding away.

Before they even had a chance to express their anger at being left in the dark, Sherlock's phone signalled an incoming text. It was from Mycroft, and it was simply an address.

"John!" he called, adrenalin once again surging, "Mycroft's found her. Let's go!"

They had wisely kept their taxi waiting and were on their way in seconds. Sherlock watched friend closely, wishing he knew the proper things to say in such a situation. He had never felt so helpless in his life. Always before in a crisis, there had been something he could do. John, his face closed and stoic, did not say a word.

The taxi stopped at the barrier the police had set up across the street. A crumpled car rested against the wall of one of the buildings by the entrance to an alley. Police cars and an ambulance were parked with no apparent rhyme or reason. A knot of officers milled in and around the alley entrance, Lestrade among them. And just as they arrived, another vehicle pulled up behind them—a coroner's wagon. Sherlock's heart stopped. He had never felt such terror in his life. He had no idea what to do as they burst out of the taxi together.

"No, no, no, no!" John cried out, running. He and Sherlock raced side by side to the entrance to the alley, only to be pulled up short by Lestrade.

"Hold on, mate," he said to John, his voice filled with compassion. "You don't want to. . . ."

Sherlock paused only long enough to check if Lestrade were still conscious, then sprinted after his determined comrade. John slid to a stop and dropped to his knees by a pile of shredded, blood-stained clothing some ways from the crashed car. Sherlock slowed and approached, dread chilling him.

It was Mary. Her face was just recognizable. The bullet had entered her temple at an angle at point-blank range and exited in the back, taking most of her skull with it. John crouched by her, his trembling hands hovering, afraid to touch, unable not to try. Sherlock leaned over from behind his friend and gently reached down to close her staring, lifeless eyes with one hand.

John took Mary's hands in his and just knelt there, holding them. Sherlock noted the jagged, bloody nails and abrasions on her hands. She had not gone quietly. Mary had fought to the last. He tried to take comfort in that knowledge. His thoughts went fondly to how formidable Mary could be, in spite of her small stature and petite build. He had more than once been silenced by her eloquent right index finger. She was a woman who knew what she wanted and how to get it; and yet was so compassionate and selfless that what she wanted was always to the good of those around her. Now he could hardly reconcile that strong, fearless young woman with this shattered, childlike wisp of fragility on the ground before him. Grief swept through him; an overwhelming sense of loss. He looked at John, dry-eyed and grim, keeping vigil over his wife of only five years, silent as the grave. How he was still upright, Sherlock could not fathom.

Suddenly, Anderson was there. He looked more sympathetic and uncertain than Sherlock had ever seen him. "I'm sorry, John. We need to secure the scene. I need you to move aside now," he said quietly. John did not seem to hear. Anderson touched John's shoulder; suddenly the ex-soldier exploded to his feet, and it was all Sherlock could do to hold his friend back.

"It's all right, John; he's just doing his job," he murmured in what he hoped was a soothing tone, although his first instinct was the same as his friend's: to stop anyone else touching Mary.

Lestrade appeared, eyes sunken with grief, and intervened. "I'd let John do what he wants, Anderson," he advised wryly, wearily rubbing his swollen jaw, "if you value your looks at all."

Anderson looked from his boss to John and nodded. "We'll work around you," he said at last. Sherlock was relieved that Anderson was actually not being a complete idiot today. If he had said anything about John contaminating the evidence, Sherlock would have punched the man himself. As if evidence of John's presence in her life wouldn't already be all over Mary.

John sank back to his knees and took his wife's hands again. His head was bowed, his eyes were closed. He became still and lifeless as a monument. Sherlock stood at his friend's back protectively, daring anyone else to disturb them. Lestrade's lot worked respectfully around them.

After a few minutes, Sherlock turned his attention to the rest of the crime scene. There was a medical team working on a bleeding man on the ground beside the car. The blade on the ground nearby was intimately familiar to him—the Italian stiletto switchblade he had given to Mary four years ago. He smiled grimly. He could see what had happened now as clearly as if he'd been present.

Lestrade stood beside Sherlock, shaking his head sadly. "She almost got away, didn't she? If the car hadn't crashed, she might have made it."

Sherlock agreed. "Mary and her captor were in the backseat. She waited until the getaway car was in a less populated area, wanting to minimize the chances of anyone else being harmed, and then lunged for the handgun. She would have known that her captors did not intend to let her go; she would have taken her chances and fought rather than meekly submit to her own murder." Sherlock walked closer to see the inside of the car. "She and her captor grappled for the gun; the driver, either trying to help his partner or merely distracted, crashed the car into the building. The impact caused them both to lose their grip on the weapon. The crack in the windshield is from an impact on the inside: the gun flew out of their hands and smashed into it. The blood smears on the steering wheel: the driver hit his head on impact, stunning him but not causing him to lose consciousness. The scuffs on the upholstery: Mary's assailant dove over the seat to retrieve his weapon. Mary must have seen where he'd put her knife. She picked his pocket and stabbed him in the back, incapacitating him, making him drop the gun again. Meanwhile, the driver recovered his senses, snatched up the gun and jumped out of the car. He physically dragged her out of the backseat, leaving his friend to slowly bleed out from his knife wound."

"He's passed out due to blood loss, but he should live to stand trial, they tell me," Lestrade told him. "Looks like the driver tried to . . . ." He grimly turned to look at Mary's body, her torn clothing telling the tale.

"Yes, I know," Sherlock interrupted, not wanting to hear the words. "You'll be looking for a man with deep scratches on his face and hands and a number of bruises. She wouldn't stop fighting him, so he. . . ." His voice trailed off, his eyes on John's back, wondering how much information his friend was taking in.

"We don't have any CCTV of the driver. And it's a rabbit warren in this area; all these council flats. It'll take us days to search them all. I'm afraid it's fairly hopeless, unless we have his fingerprints on file with a current address, and he's stupid enough to go home," Lestrade continued.

Sherlock nodded thoughtfully. "Mycroft's people are on it. We'll find him."

Anderson approached them now, nervously. "Uh, sir. We need to . . . transport the body now. Can you . . . ?"

Lestrade shook his head firmly. "I've had my turn," he said ruthlessly, rubbing his jaw again. "Do your job, Anderson, and take the consequences."

Anderson hesitated, and Sherlock found himself sympathizing with the man against his will. Having been on the receiving end of one of John's right hooks himself, he couldn't blame anyone for wishing to avoid incurring his friend's wrath. "I'll take care of him," he stepped in, and Anderson gave him a rare look of gratitude.

Not wishing to startle John into sudden action, Sherlock stepped around Mary's body so that the vigilant soldier could see him. "John," he said gently, "they have to take her away now." John seemed not to hear. Sherlock crouched down to eye-level with his friend. "John," he coaxed, "look at me."

Slowly, John's head swivelled up and their eyes met. The depth of pain in John's strained face took Sherlock's breath away for a moment. He regulated his breathing and tried again. "They have to take her away now, John. We need to go."

John looked like a man waking from a nightmare. He didn't move for a long moment. Then he gave a tiny nod and rose to his feet. He took two steps back and straightened himself to his full height, taking refuge in his military training, keeping in perfect control of himself. Sherlock's heart ached for him, almost wishing the man would break down and weep instead of being so impossibly brave. He stepped to John's side and the two watched as Mary's body was zipped gently into a body bag and placed on a stretcher. Only then did John turn to Sherlock, and now his eyes blazed.

"Find him," he grated out between clenched teeth. "Sherlock, find him. Find. Him."

"Mycroft has his best people on it," Sherlock assured him.

John shook his head. "You have resources Mycroft has no access to. Find him, Sherlock. For Mary."

Sherlock nodded. John was right. His homeless network had a better chance of finding this man than all of Mycroft's fancy technology had. He turned to Lestrade, who had remained standing near.

"Yeah, I'll take him home. You do what you have to do to get this bastard. And my people will be looking as well, of course," Lestrade said without being asked. "Try to take him alive, Sherlock," he added. "Although I can't say I'll be looking into it with any great scrutiny."

The corners of Sherlock's mouth twitched in a grim smile and nodded his appreciation. "Not home. Baker Street. Mrs. Hudson."

"Right. Come on, mate. We'll go get some tea, shall we?" Lestrade led John gently away.