"Bullseye! Come back here, you idiot!"

Victor swears as the dog takes off across the Coe Fen. He looks down at the leather loop that has been left dangling on his wrist; the bull terrier has chewed its way through the leash.

"You stupid bitch!" A pair of students walking towards him giggle at the epithet, and Victor blushes and then shrugs apologetically. "Well, she's a female dog, so it's justified."

One of the two girls laughs as her glance sweeps him up and down in appreciation. Six foot five and built of solid muscle, Victor's blond hair, trim waist and blue eyes usually work a treat on women.

But, apparently not on the canine variety – Bullseye is already a hundred yards away, head down in a cow pat and chomping enthusiastically.

"Don't eat that; it's disgusting! Come back here!" Victor fumbles in his pocket for a whistle, and begins blowing it furiously as he charges after her. The white dog with a black patch around its left eye pays absolutely no attention and continues eating as he approaches. This is one of her nastier habits; his fiancé Chloe had explained that bitches are attracted to eating faeces because that's what they do to clean up their puppies. Victor had told her to break the dog of such a habit if she wanted to kiss him after the dog was allowed to licked her face.

"Steady there; who's a good girl?" He tries to use a calm voice, so as to not frighten her. But, when he lunges for the length of damaged lead dangling from her collar, she senses his intent and runs off, the broken strap flapping on the ground behind her.

"Fuck!" He closes his eyes in disbelief. "I so don't have time for this."

He'd left the flat with what he thought was plenty enough time for the dog to shed her excess energy and do her business. He is supposed to be on his way to rugby practice, where he was planning to dump the dog with one of the ground staff who is besotted with her and happy to keep her occupied for the duration of the practice.

The route he usually jogs to the ground on Grange Road crosses the Cam River from his flat on Saxon Street. It is a lovely run at this time of the year, the autumn's crisp afternoon sun touching the trees with colour. This late in the season the grass pasture is eaten well down by the cattle that are allowed to roam the common land, an odd reminder of the countryside right next to the famous Cambridge backs*. In another couple of weeks, the livestock will be gone, and he won't have to dodge them and their shit when he runs to the practice sessions.

On this occasion, Victor had tried to get the dog to run with him, but it had stubbornly refused. Trying to encourage the dog as it dragged behind him, leash firmly clamped between her teeth, fighting him every step of the way, slowed him down to a walking pace, and now he has no contingency left.

I am going to be chewed to bits by the coach. As the University Blues team captain, it is up to Victor to be a role model and being late to practice is going to get him a right ear-bashing. It won't even be the first time, he fumes at having to look after the bloody dog. He doesn't even like the thing; he's already been in trouble because of it – only yesterday Bullseye had attacked a Pekingese walking on the Parks. Victor had to pay a fine and listen to the Community Support Officer's lecture about dangerous dogs, which he repeated at length last night on the phone to his absent fiancée. She already has one recorded black mark against her; one more and she'd be banned from the University Grounds. The dog, that is, not Chloe. It is just his luck that his fiancée's eldest sister, Sophia, who normally keeps Bullseye at home while Chloe is at university, is getting married in a month. Both sisters are now away for four days on a hen party trip to Ibiza, leaving Victor with the unenviable chore of walking the beast.

Chloe always tells him that he'd get more with honey than with harsh words, so he shouts after the dog again: "Bullseye; here, girl! I've got a biscuit," waving it in his hand. The ASBO dog ignores the incentive; she doesn't even turn to look, and keeps on going as fast as her legs will take it.

Victor sighs and breaks into a run. At least she is headed in the right direction. They'd already crossed the Cam River on the footbridge by Robinson Crusoe Island and the dog is now running toward the Mill Pond. Naturally, she doesn't mind the boggy ground, and is angling across the field that way. Victor picks up the pace, but he can't venture far off the path into the sinking, soft earth without risking an injury running this fast. On the firm sand of the path, it is easier to lengthen his stride. He might be a second row forward, but he can still put on plenty of speed. He should be able to cut her off at the pass.

The narrow bridges at Mill Pond form a bottle neck, so he starts shouting as the dog weaves between the pedestrians approaching them. "Someone stop that dog!"

Victor begins to worry about what might happen if she gets onto the roads on the other side. Newnham Road is very busy; if she gets hit by a car, he has no idea how he is going to explain it to Chloe. At times, he swears she loves the dog more than she does him.

He loses track of Bullseye as she disappears into the crowd of students and pedestrians. He spots two pushchairs with toddlers in them, and pants a prayer between strides that the dog won't crash into either of them. He is about twenty yards away when there is a shout and a strangled cry of pain from somewhere in the crowd that has formed just on the other side of the bridge, outside the Bella Italia wine bar.

Soon, yelling can be heard: "Get it off him! Grab the lead!"

Victor sprints across the bridge and starts pushing his way through the crowd. When he reaches the epicentre of it, the scene is something out of a nightmare: Bullseye has sunk her teeth into the left leg of a dark haired young man who is bent over trying to pry her jaws off. A middle-aged woman has grabbed the severed leather lead and is trying to drag the dog away from him. The dog just hangs on and clamps its jaws even tighter and deeper into the leg roughly where the calf muscle start.

"Bullseye! Off! Let him go!" Victor runs forward, grabs the dog by the scruff of her neck, just as the young man staggers and his backpack full of books slips off one shoulder, unbalancing him.

He falls hard. Crazed by the furore and the sight of her prey now brought down to her level, the bull terrier growls, closes its eyes and just bites down harder.

Frightened, the woman holding the remains of her leash lets go of it and backs off, as Victor again shouts "No!"

It has no effect; Bullseye shakes her head violently from side to side, as if to finish off what she has captured. Her victim cries out in pain, and there are shouts of horror from the crowd.

Without thinking, Victor grabs the dog's jaws and tries to pry them apart. Soon stunned by the strength of the canine's grip, he applies all the force of a University first team rugby player to those jaws, and when even this yields no results, he resorts to kicking the dog's soft underbelly. Winded by the blow, Bullseye squeals and lets go, which allows Victor to finally drag her away by the collar. The crowd backs away from them, scared by the sight of the bloodied teeth in the dog's slavering mouth. Victor grabs the remnants of the leash and then lashes it to the metal railing on the bridge – a double knot that will only tighten if she starts to pull on it.

Victor then turns back to see what damage the dog has inflicted on her hapless victim. Even as he kneels beside the young man, Victor knows that this is probably a university student: the science textbooks that have spilled out of his backpack are proof enough of that, as is what looks like a Trinity College scarf. But, the student is very young; probably a Fresher. The boy's eyes are closed in pain as he grips the back of his left leg.

"I am so sorry; the bloody dog is a menace, but I never thought she'd hurt anyone. How bad is it?"

The boy opens his eyes, lifting his hand away from where the dog has bitten right through the trousers. The hand is bloody.

Victor groans. Worry now fans the flames of his rage at the four-legged perpetrator. He mutters under his breath, "I'm going to beat that dog senseless."

"No!" the boy instantly protests, "it isn't her fault!" He doesn't look at Victor, but clamps his hand back down hard on the wound. "I was afraid she'd run into the road, so I stepped on the lead as she ran by. The force of it nearly throttled her. She attacked what she thought had hurt her. Don't blame the dog; please don't hurt her any more than I already have."

Victor heaves a sigh of relief at the unexpectedly lenient reaction. "What can I do to help?"

One of the women with a pushchair comes forward and crouches down. "I know some first aid; let me take a look." Without being asked, she takes hold of the torn trouser leg and rips the cloth away to expose the wound.

Victor gasps. The dog has opened a great gash starting at the calf muscle and going a long way down towards the foot. It is very deep, the gaping flesh mangled and torn, and there is an odd white sinewy bit hanging loose. Blood is flowing from the injury – not exactly gushing, but enough to scare him badly.

The woman blanches, too, turning to the crowd of onlookers. "Someone call an ambulance, now! Does anyone have a clean piece of cloth? I need to apply pressure."

The boy slips his college scarf from his neck and hands it over to her. "Use this; it's new." Victor is surprised at how calm he seems. If their positions had been reversed, he knows that he'd be cursing a blue streak, or would have already passed out. He's never liked the sight of blood. It is a standing joke on the rugby squad; he would turn pale at the sight of someone with a broken nose or gashed face in a scrum.

Someone in the crowd calls out: "That dog is a menace, and should be put down. I'm calling the police to get it taken away."

The woman wads up the scarf and applies it to the wound, then addresses the crowd. "This will have to do until the ambulance gets here."

"No. No police, no ambulance," Bullseye's victim insists.

Surprised by the vehemence of his refusal, she argues: "You need medical treatment. Stitches at least, and careful cleaning." She checks to see how much blood had oozed into the scarf. "Definitely a job for an Emergency Department; that's probably going to need surgery, and antibiotics. Oh, and tetanus-"

He argues back; "No hospital. There's a doctor only three minutes from here – the Newnham Walk Surgery. I'll go there." He grabs the scarf out of her hands and then ties it around his leg, shooing her away from him. "I'll be alright; just stop fussing." He starts to get up.

Victor is torn. If the boy doesn't think it is as bad as it looks, then maybe the incident won't be reported. On the other hand, the wound looks terrible, and he feels awful that Bullseye had been the one to do it. It is his fault; he is responsible for this disaster.

Once the injured boy struggles to his feet, he starts collecting his books and picks up his backpack. When he starts to hobble towards the road, Victor calls out. "Wait; I'm coming with you."

Without turning around, the student replies, "Look after the dog. You can't leave her tied up like that; she'll get distressed if you leave her."

Victor ignores that and catches up with the boy. "You're more important than she is."

The boy does not have time to respond, because his wounded leg suddenly crumples beneath him and he falls again. This time, Victor is close enough to catch him. Even as he does, he realises that the boy has fainted.

After that, things happen so quickly it is a blur.

"Has anyone got a belt? I'm not wearing one." The woman is beside him trying to stem the flow of fresh blood; this time it is positively gushing – getting up and walking with the injury had obviously caused more damage. Victor is wearing a pair of joggers; the elasticated waist offers no help.

A hand pokes through the crowd that had moved to surround them and she grabs the proffered leather belt, applying it as a tourniquet. Victor can hear an ambulance siren in the distance – probably from Trumpington Street. It appears that someone had called for one after the young man had collapsed – Victor has been too preoccupied to notice the call being made. The siren's wail becomes clearer as it turns onto the Fen causeway to cross the river, and louder yet as it comes through the roundabout onto Queen's Road.

The crew is beside them in minutes, one of them asking questions of the woman about whether the victim had hit his head when he fell, and what exactly had happened. As soon as the professionals had showed up, she'd gone back to the pushchair to try to calm her little boy, crying because of the siren noise.

After getting their patient into a recovery position, one medic busies himself putting on a pressure bandage, and the other gets an IV running. "Anyone know his name?"

Victor goes through the boy's backpack. He finds a notebook, with a name written in it. "Holmes, initials WSS. He's a Trinity College student." There is an address: Burrells Fields, one of the college residential blocks. He reads the details out to the ambulance staff.

"Mister Holmes. Can you hear me?" The paramedic taps Holmes's face, then presses above his eye socket. There is no response at first, but eventually Victor sees a ridiculously long pair of lashes on the boy's pale cheek flutter. The two men lift Holmes onto a trolley and he is wheeled onto the ambulance, still semi-conscious. It goes off the concrete in front of the wine bar and into the road, the siren and blue lights parting the morning commuter traffic.

The woman goes back to her pushchair and pats her little boy's head. "Let's go home, Geoff; that's enough excitement for the day. Mummy's been a good first aider, and you've been a brave little boy to put up with all the commotion."

The crowd starts to dissipate, and as it thins, Victor can see where Bullseye is sitting, still tied to the bridge railing, wagging her tail at the people passing by, looking like nothing has happened at all.

A thought creeps into his head; if he just takes her home, and makes sure that she is never seen in Cambridge again, he (and she) just might get away with it.

As if he had said this aloud, a voice comes over his shoulder. "I'm still going to report this to the police. People like you with your dangerous dogs – you're a menace to society." An elderly man carrying a camera walks around him to take a photograph of Bullseye. Probably a tourist, but there is no way that Victor would take a chance that the man isn't being anything but determined in his decision.

Raising both of his hands as if in surrender, Victor reassures the bloke: "Don't worry; I'm going to do the right thing." Even if the guy hadn't threatened exposure, he isn't that kind of shit who would run away from this sort of mess, whatever his initial thought might have been.

He picks up the backpack and the scattered library books, then goes to untie Bullseye.

He needs to get his priorities straight. He'd have to go back to his flat to take her home, then he'd call the coach and tell him that he is off to the hospital; this is more important than missing a practice. As he walks back across the fen to the footbridge over the Cam, he keeps thinking about the student. Despite his obvious pain and distress, Holmes had been more concerned about the dog than himself. Victor feels embarrassed, almost ashamed of his own behaviour. He feels compelled to know more, to understand how someone so young could be so rational and calm. Even though the circumstances of their meeting are far from ideal, Victor cannot help but think that something extraordinary has just happened to him.

"Come on, Bullseye. We've got important things to do."

This time the dog trots obediently alongside him as they make their way across the field.

Notes:

Author's Notes: *"The Backs" is an area of Cambridge to the east of Queen's Road, where six of the university colleges back onto the River Cam, their grounds covering both banks of the river. The fronts of the colleges are all onto Trumpington Street which turns into King's Parade, but their "backs" go down to the river. The Coe Fen is used for common land grazing by cattle; it and Sheep's Green/Lammas Land to its south are reminders of Cambridge's agricultural heritage.