Nobody could have anticipated the horror that unfolded in Leicester Square on a sunny summer morning little more than a year ago.
Shortly after 11.30am on August 12, 2024, an attacker grabbed an 11-year-old girl in a headlock and repeatedly stabbed her with a steak knife.
The suspected knifeman - Romanian national Ioan Pintaru, 33, now facing trial for attempted murder - was wrestled to the ground by two uniformed men who had raced to the scene.
Such a nightmare scenario playing out in broad daylight seems scarcely credible, especially in one of the busiest spots in London's West End.
To many, though, it is even harder to fathom that the heroes in uniform weren't members of the Metropolitan Police.
In fact, they were employed by a private force drafted in to fight crime in a corner of the capital that attracts 2.5 million visitors a week to its theatres, cinemas, pubs, restaurants and shops.
It is a trend that is increasingly evident across Britain and follows the realisation almost a decade ago by a future key figure in the industry that 'the thing missing from policing was police officers'.
The growing presence of private bobbies comes against a backdrop of dwindling confidence in traditional law and order. Among the biggest concerns is the shoplifting epidemic, which is costing high street stores an estimated £2.2billion a year. The 530,643 offences logged last year amount to a 20 per cent increase on the 2023 figure.
Meanwhile, the lack of a regular police presence in many areas and the failure to properly investigate crimes such as burglaries have also emerged as major issues.
Yet the first signs of a move towards private policing in Britain date back to 2016 and the founding of My Local Bobby, the employer of the two men - named only as Youssouf and Darren - who came to the rescue in Leicester Square.
The company, set up by David McKelvey, a former Met detective chief inspector with a background in tackling organised crime gangs, now has 150 bobbies identifiable by their distinctive red livery and 24 'very experienced' plain-clothes detectives on its books.
It started out operating in exclusive areas of London such as Belgravia and Kensington but has since expanded to cover dozens of residential and business 'beats' across the capital as well as parts of Essex, Suffolk and Hertfordshire.
Under existing legislation, members of private police forces - like the general public - can only carry out a citizen's arrest either to prevent a crime or if they catch someone committing an offence. The Criminal Law Act says 'reasonable force' can be used if a suspect is being violent or aggressive.
Mr McKelvey told The Mail on Sunday that he set up My Local Bobby after noticing that 'you didn't see police officers on the streets any more'.
With monthly household subscriptions ranging between £30 and £125, the 63-year-old explained: 'A group of residents get together and pay for the service. That service is tailored to their needs - whether it's eight, ten, 12 hours or 24/7.'
'They get their own bobby, someone they get to know and who gets to know them, knows what cars they drive, when they put their bin out, makes sure that stuff delivered from Amazon isn't left on the path, checks their cars are locked at night, windows closed and so on.
'When a bobby comes on duty, he'll check there's no graffiti, no littering. We deal with everything - street lighting, broken paving stones, whatever. It's not just about an area being safe; it's about an area feeling safe.
'If somebody has fears about someone in the area committing crime or antisocial behaviour, they just let us know and within minutes one of our bobbies will be there. The difference compared with the majority of other security companies is that our bobbies will intervene, will detain and will arrest.'
Each 'beat' has its own dedicated mobile phone number on which the bobby on duty can be contacted directly. There are also WhatsApp groups to allow subscribers to share intelligence and images relating to suspicious activity. Meanwhile, CCTV recordings - including individual household footage - are monitored on a round-the-clock basis by staff in the control room, known as 'the Citadel', at the firm's Waltham Abbey headquarters in Essex.
Mr McKelvey said his staff, who get twice-yearly training in using handcuffs and restraints, include high concentrations of ex-police and military personnel. 'In every beat we operate, we have become the first responders,' he said. 'Very rarely now do our communities call the police first - they'll only call the police after calling our bobbies.'
'Nine times out of ten, our bobbies will deal with anything. They'll deal with stabbing and knife crime, they'll deal with shoplifting, homelessness, drunks, they'll deal with violence.
'Last week we dealt with two blackmails... we're dealing with absolutely everything, down to retail crime, shoplifting, pickpockets, stuff the police don't respond to. But this isn't the fault of the police; this is down to lack of funding.'
Indeed, the Met has lost some 1,000 officers in the last year alone.
No wonder that a landmark review published last month showed that public confidence in the police has fallen to a historic low over the past decade. Of 32,000 Britons who were polled, only 49 per cent described their local force as doing a 'good or excellent job' in the 12 months to March. The figure from the Crime Survey for England and Wales was down by 13 percentage points - from 62 per cent - a decade ago. Other findings show that only 11 per cent of people said they had seen an officer on patrol at least once a week - compared with 29 per cent ten years previously.
The proportion of crime victims who said they were satisfied at how police handled the matter - 51 per cent - was the lowest since records began in 1992.
Elsewhere, statistics show that just 5.7 per cent of reported crimes were solved in 2022 compared with 29 per cent in 2010.
Meanwhile, a recent poll indicates that only around half of us have spoken to a police officer in the past 12 months - although even that figure seems high compared with anecdotal evidence.
Among My Local Bobby's commercial clients are a number of business improvement districts (BIDs) - including The Junction BID, which represents around 400 businesses in Clapham Junction, south-west London. Jonny Dyson, a board member of the BID, said the decision was made to sign up to the service amid 'the increasing rise of shoplifting and the decreasing visibility of police on the streets'.
He said: 'I'm 57 and certainly when I was younger you'd see a lot more police around. You hardly see them now; they’re closing down police stations left, right and centre.
‘It just feels like when it comes to petty crime everyone is just accepting it. There’s no deterrent; there’s nobody stopping anybody. So I suppose [having] the bobbies for us is trying in some tiny way to win back that space that’s being ignored by the proper police.’
One householder living in a My Local Bobby residential area said: ‘Regardless of where you live it seems to be accepted now that the police are unlikely to be much help for the sort of criminality and antisocial carry-on that affects neighbourhoods and communities. So it just feels like a bit of a no-brainer to have access to private policing if it is available.’
The firm has been operational in Hutton Mount, a suburb of Brentwood in Essex. It claims that since the start of the year just two incidents have been reported, compared with 314 crimes - including 55 car thefts and 13 residential burglaries - recorded during the same period in the wider Brentwood area.
Several other private policing firms have followed My Local Bobby's lead. Among them is Blueline Security, which mainly operates in the Home Counties.
Others include Dorset-based Safeguard Force, which claims to be 'making strides in enhancing community safety by patrolling hotspot areas, collaborating with local police and raising awareness of their presence'.
According to its website, it is made up of more than 200 volunteers from 'diverse backgrounds including security professionals, ex-military personnel, first aid responders and concerned residents'.
Meanwhile, Birmingham-based The Shield, which bills itself as 'working across the UK to prevent harm in your community before it happens', claims to have surveillance intelligence experts and 'special ops' personnel in its ranks.
Yet not everyone is convinced that private policing is such a clever idea. A long-term resident of one of west London's more genteel enclaves told the MoS: 'We were offered a policing service where I live and, after thinking about it, we turned it down on the basis that it could potentially act like a beacon for criminals.
'If they see private police around, they're presumably going to think there will be rich pickings to be had.'
For his part, David McKelvey stresses there is no mystery to his business model: 'There is a gap in policing and all we've done is come along and fill that gap.'