The ad, which breaks next week, forms part of the NSPCC's autumn "someone to turn to" campaign, which highlights the fact that thousands of children suffering abuse across the UK don't have anyone to talk to.
The 60-second spot portrays an eight-year-old girl as a puppet being controlled by a ventriloquist, who is also her abuser. She sits powerless on his lap in the classroom, unable to respond when the teacher asks her a question.
When another child comes up to her in the playground and asks her if she wants to go and play with her, the little girl's mouth moves, but it is the man's voice that says: "No."
The spot concludes by asking viewers to call a freephone number to help the NSPCC end cruelty to children. The endline reads: "Abused children can't speak up."
The NSPCC director, Mary Marsh, said: "The NSPCC depends on public support to help end cruelty to children. We want people to help us achieve this mission by taking a range of actions including donating, fundraising or campaigning with the society."
The ad was written by Leo Premutico with art direction by Ian Jacobs.
The production company was Large.
The ad is aimed at all adults and will be shown around primetime terrestrial and satellite programmes. Media planning and buying is through ZenithOptimedia.
The Saatchis chief executive, Kevin Dundas, said: "'Full stop' is one of the country's most powerful and important charity campaigns. This latest initiative is a key milestone in the quest to stop cruelty to children.
It will help focus the public's minds on where the greatest threat to children lies - and it does so in a powerful, emotional and original way."