What would you do if you saw a little girl alone on a busy street where she clearly had no place being alone? Would you ask her where her mummy or daddy was? Or just ignore her and walk on by?
Well, according to hidden camera experiment for a TV documentary the vast majority of us - perhaps because we fear being labelled a 'stranger danger' - would turn a blind eye.
In fact, in one hour, 616 passers-by simply ignored Uma, seven, and Maya, five, who took it in turns to look lost.
The older child was clutching her favourite toy while her younger sister was sucking her thumb – and both looked utterly lost and forlorn.
The girls stood for an hour on a Saturday morning in a busy shopping arcade looking for 'help', as part of a social experiment for television.
As their mum watched from a distance, passing couples even split apart to walk around either side of the 'lost' girls and people wheeling suitcases took evasive action to avoid Maya and Uma, without checking if they needed help.
ITN researchers chose Victoria Place shopping centre, next to London's bustling Victoria Station, to test the British public.
Maya and Uma agreed to help and were brought along by their mother Reshma Rumsey, who watched from behind a nearby pillar with a presenter.
Uma went first, standing alone in the middle of the concourse, holding her pink doll and putting on a good act of being scared and vulnerable.
After 20 minutes, not a single person had stopped to ask the seven-year-old if she was all right, even though some of them had plainly seen her.
Next, it was her five-year-old sister's turn. Maya stood sucking her thumb, and then tried kneeling down, gazing up forlornly at passing shoppers, but she too seemed to be invisible. Eventually, a pensioner gave her a concerned look.
At first, Pearl Pitcher, of Kent, who is in her seventies, carried on walking, but she soon turned around and came back to ask Maya if she was waiting for somebody.
Mrs Pitcher said later: "She had stood too long by herself and no parent or friend came up to see her. I was very hesitant to come and ask her, and I walked past but I thought I must come back – just in case.
"I think the older generation would stop, but very cautiously, a bit like I was. I don't know about the younger generation. A lot of people walked by and didn't take any notice at all."
Mrs Rumsey, a 39-year-old journalist, said she was 'gobsmacked' by seeing her daughters ignored by so many people.
She said: "When you see that little face looking so lost, and people are walking past, it is awful.
"I did not expect so few people to stop ... it's shocking that people noticed a child on her own and they just walked past, whether it's through fear or because they didn't care or because they didn't notice.
" As a mother, to watch your child on their own, looking lost and needing help and watch people walk past is heartbreaking."
The NSPCC said a child's welfare was more important than worrying about being labelled a 'stranger danger'.
A spokesman said: "We have got to get a message out to adults that they have a responsibility to protect children and that must supersede any concern you have for other people's perception of why you are reaching out to help that child."
Little Girl Lost: A Police 5 Special will be shown on Channel 5 at 6.30pm on Tuesday, March 25.
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