Frankly, to any modern responsible parent, it sounds tantamount to child abuse.

Who in their right mind would bring a five-year-old boy — and one who has never even been to a big city — to London, put a map in his hand and wave him off?

Who would leave this child — able to distinguish his left from his right, but only just — outside the Imperial War Museum and tell him to find his own way to the London Eye, by bus?

His only companion will be his cousin, who is also five. Actually, it would be considered highly neglectful, were it to happen for real. London bus drivers are instructed to alert the authorities if they suspect a young child is travelling alone.

Kieran Robinson, five, and cousin Rita, six, pictured together, managed to navigate their way from the Imperial War Museum to the London Eye without their parents helping them

The cousins, pictured together on a bus, ask a lady at the stop for help and are on their way after stopping to play on the slides at a play park

This situation would be a Code Red, in London Transport speak, and the police would be called.

That they didn’t in this case was because it was a meticulously planned social experiment, for an ITV show investigating how much freedom we give our children — and whether they could benefit from more.

In this particular case, seven children (three groups, aged from four to seven) were set the task of getting themselves across the busy capital unaided.

Planet Child, hosted by doctor twin brothers Chris and Xand Van Tulleken, contrasts the freedom given to children in other parts of the world with the rather wrapped-in-cotton-wool existence British children have.

Are we too protective? We are reminded that most British kids are so heavily supervised that they spend less time outdoors than prison inmates.

In the show, we find out how other cultures do it. We meet a six-year-old in Tokyo who routinely travels alone across the city to get to school.

In Namibia, we are introduced to a seven-year-old and his five-year-old brother who walk miles from the safety of their village, not an adult in sight. They may not have to negotiate traffic, but they do have to be alert to wild dogs and elephants.

Rita and Keiran, pictured, live on a farm in rural Yorkshire and Keiran's mother said he had never 'been to anywhere bigger than Skipton' before the TV experiment

Another world? Certainly, in the UK, our parenting style is much more hands-on.

‘I think we were interested in the fact that children get treated very differently around the world,’ admits Dr Xand. ‘We wanted to see if the assumptions we make about parenting in the UK could be challenged.’

Dr Chris adds: ‘It’s about kids and how they behave. We provoke them and put them in weird situations — and we’ve found it’s surprising how they respond.’

In Planet Child, children are asked to take part in a range of experiments, from climbing trees to going shopping, to assess their attitude to risk and their ability to cope without adult supervision.

The London experiment is the most radical. So how do the children get on?

Well little Kieran Robinson and his cousin Rita, who live on a farm in rural Yorkshire, almost fail at the first hurdle when they succumb to the lure of the play area in the Imperial War Museum Gardens.

At the point where the production crew think they should be boarding the allotted bus, the pair — oblivious to any idea of timetables — are having a whale of a time on the slides.

Laura Robinson, Kieran’s mum, was kept updated on her son's travels around the capital by film crew and said she had her 'heart in her mouth' the whole time. Keiran is pictured with a map

Laura, pictured with son Kieran, brother Kevin Robinson and his daughter Rita, admitted that she spent much of the experiment thinking 'what have we done'

Doctors Chris and Xand van Tulleken, pictured, present the series and Dr Chris admitted he is now less of a ‘helicopter parent’ with his own toddler daughter after doing the experiements

What happens when they do finally leave? Well, your heart is in your mouth watching the two little figures heading into the heaving city streets, and trying to find a particular bus stop.

They ask a lady at the bus stop for help. Clever? Or downright worrying, given our preoccupations with Stranger Danger?

Of course, the children were never in any actual danger during the filming. Their parents had been asked to allow them to take part with full assurances that they would never be entirely alone — although, crucially, the children were not told this.

The London bus they would be getting on was rigged with cameras which would follow their every move. Adult ‘minders’ would be there, at a distance, posing as passengers.

At the first sign the children were distressed, they would quickly intervene.

Nonetheless, it makes for tense viewing. Perhaps the most astonishing thing is that the adults never have to step in. The children really aren’t fazed by the task.

There are a few bumpy moments. They aren’t told when to get off the bus, and there are some panicked little faces as they see the London Eye come into view, then go out of sight again as the bus follows its route.

Becky and Tim Rose's four children, pictured together, are also seen in the show. The oldest twins seven-year-old Darcee and Judah were also set the London bus challenge

As a viewer, it’s excruciating. How can these kids possibly negotiate all this?

Without giving too much away, they do — much to their delight, and the adults’ astonishment. They just got on with it, admits Dr Xand. ‘Left to their own devices, they do what they are asked to do.’

What about their parents, who were not able to follow their children’s progress on camera and had to rely on updates from the film crew? Suffice to say, they were all a bag of nerves.

‘I spent a lot of the time thinking: “What have we done?”’ admits Laura Robinson, Kieran’s mum.

‘Having grown up on a farm, Kieran maybe has more freedom than most. He can go out and play in the fields. But although he’s very independent, he’s never been to anywhere bigger than Skipton, and even then I won’t let go of his hand.’

Waving him off in London was something else. ‘I was worried about the traffic. The crew kept us updated with how they were getting on — “They’ve got on the bus now”; “They are fine” — but our hearts were still in our mouths. When we saw their heads bobbing towards us at the London Eye, I was so relieved.’

Becky, pictured with Tim and children Darcee, Judah, Jaxon and Hudson, said she didn't know if her children could read a map as they'd 'never been in a situation where they’d need one

Becky and Tim Rose, both 45, live with their four children in Horsham, West Sussex. They have two sets of twins, Darcee and Judah, seven, and Jaxon and Hudson, three.

All four were involved in the series, but it was Darcee and Judah who were set the London bus challenge. Their parents admit they balked when it was explained to them.

‘There is no way we’d ever let them out of our sight,’ says Becky, who works in marketing. ‘I suppose we do live in a bit of a cocoon, but we’re certainly not unusual. It’s just the time we are living in, isn’t? You are aware of Stranger Danger.’

The pair say their hearts were racing when they had to kiss their children goodbye. They were also alarmed when the film crew handed Darcee and Judah maps.

‘I knew they didn’t know how to read a map,’ says Becky. ‘We’d never been in a situation where they’d had to read one.’

She fretted that she wouldn’t be ‘there to read their reactions, to see if they were distressed’, adding: ‘I just didn’t know how they would cope, I had visions of them dissolving into tears, saying: “I want my Mummy.” ’

Judah and Darcee, pictured in a park, enjoyed their big adventure in London and displayed the most extraordinary team-work, pitching in together to work out where to go and what to do

In another experiment an assault course is set up for Darcee and Judah and their brothers in the garden. Then random equipment is left near a big tree and the children can do as they wish

Interestingly, while some of the parents involved were reduced to tears during the experiment, none of the children was.

There were other concerns, too, Becky laughs. ‘As twins, they are very close, but they do bicker a lot. I worried that they’d fall out, and all the cameras would capture would be a long argument.’

They were surprised and delighted by how it actually panned out. Darcee and Judah displayed the most extraordinary team-work, pitching in together to work out where to go and what to do.

As for crying for their mummy? Pah! The intrepid young pair were far too busy enjoying their big adventure.

So it was, too, with the largest group in the experiment. Claire Lewis, 33, is a single mum to Leo, Abi and Harleigh, who were seven, five and four respectively during filming. They live in Margate, and Claire admits she is more protective than most.

‘I suffer from anxiety and I don’t let them go out on their own, even to play on the street in front of the house,’ she says.

‘I always think the worst is going to happen — that a car is going to go into them or someone will take them.

Since the TV show the Roses, pictured together in their garden, said they have made an effort to allow the children a freer rein

‘I had much more freedom when I was their age, and I do worry they don’t have enough. Leo will be going to secondary school in a few years, and he’ll have to be able to get the bus.’

This experiment was clearly an ordeal for Claire. Her biggest worry was that Leo, who can get irritated by his little sisters, would ‘stomp off and leave them’. In the event, Leo was a star, a whizz at navigating the little posse through the gardens, to the bus stop and onto the bus.

He has the zeal of a military commander, the Van Tulleken twins say, as he briskly reads his map and identifies landmarks.

Who knew? Certainly not his mum. ‘I’m so proud of him, and it did make me realise that I need to give him more freedom,’ she admits. ‘Since we finished filming, he has been allowed to go to the corner shop. You can’t keep them wrapped up.’

This is the most remarkable part of this series: watching adults question, mostly for the first time, how they parent.

Most of us wouldn’t identify ourselves as helicopter parents, always hovering, yet most of us are. But is our constant refrain of ‘stop, you might hurt yourself’ actually damaging our children by holding them back?

Claire Lewis, 33 and her children Leo, eight, Abi, six, and Harleigh, five, also appear on the show and the mother worried her son would get annoyed with his sister during tasks

Leo, middle, was a star at navigating the his siblings through the gardens, to the bus stop and onto the bus when they were set the task of getting around

‘The thing that amazed me was how much the kids got from doing this epic thing on their own,’ says dad Tim Rose. ‘When they came bounding towards us, having succeeded, they were buzzing that they had achieved something amazing. They were so much more confident.’

There were other experiments that weren’t quite so epic, but fascinating nonetheless.

One takes place in the Roses’ garden. An assault course is set up for Darcee and Judah and their little brothers. Then random equipment is left near a big tree — and the parents are asked to let the children get on with it. Cameras record what happens next.

‘There was a ladder,’ says Becky. ‘I knew immediately that the older two would put it against the tree. Then Darcee started to climb.’

Never had the older twins attempted to climb this tree. ‘And if they had, I would have gone running out to say “stop”. This time, Darcee got halfway up before she said: “It’s not stable”, which was a relief. It meant she was aware of the danger.’

Doctors Chris and Xand van Tulleken, pictured with child models, said parents 'underestimate children constantly. They are capable of far more than we think’

Darcee continued, cautiously, until she was high in the tree. No one fell that day. There were no trips to A&E. But there were children punching the air with how much they had achieved.

Since then the Roses, like the other families, say they have made a concerted effort to allow the children a freer rein. ‘We’ve been blown away about how much it’s made us rethink things,’ says Tim.

Can we all learn from this programme? Dr Chris admits he is now less of a ‘helicopter parent’ with his own toddler daughter. ‘Now, I don’t assist her coming down a short flight of stairs because if she falls down two steps, she’s less likely to fall off a building or off a wall when she is confronted by those [as she will better assess the risks].’

Bottom line, we are unlikely to kill our children by letting them climb a tree; but we might be putting them in danger by failing to let them learn how to climb.

‘If you look at the statistics of child fatalities, the vast amount of incidents are around things like car accidents,’ says Dr Chris. ‘They don’t generally die in playgrounds, falling off swings.

‘We underestimate children constantly. They are capable of far more than we think.’

ITV’s Planet Child starts on Wednesday May 1 at 9pm.