The campaign includes direct mail, door-drops, inserts and DRTV using the computer-generated creative cartoon-like images from the Saatchi & Saatchi TV campaign.
It will run until October 10 and supports the "Talk 'Til it Stops" initiative, which launched above the line on September 19.
The integrated mailer uses the Saatchi & Saatchi images and on the back of the envelope a child used in the ads appears to be talking through an NSPCC green bubble saying "John talked, Vijay talked, Natalie talked".
Inside the envelope, the supporting letter is headed "And we listened", informing recipients about the 24-hour child protection line and asking them to donate £2 a month.
The leaflet on which the green speech bubble appears expands upon the stories of John, Vijay and Natalie, based on real case studies of calls to the helpline.
Mailers will be sent to 1.4m names from in-house and cold lists.
The door-drops, again using the Saatchi & Saatchi creative, will target 14.7m UK households asking recipients to "Read your pack". Buying was done through WWAV Rapp Collins.
In addition, 4m inserts will appear in publications including Grazia, Zest, Woman and Home and as a third-party insert with catalogues such as Cotton Traders.
It consists of a piece of paper, rolled so that the first view is of the words "help me please" scrawled in a child's handwriting. It opens to tell the story of Andy, who was kept in isolation and beaten.
The supporting letter explains that Andy's story is just one of the many the NSPCC hears every day, and asks the recipient to give £2 a month to help fund its services.
The DRTV drive will feature the existing NSPCC ads but with increased number of showings on daytime and early peak lots on multichannel and terrestrial including ITV regions, Five, Sky News and UK Style.
Marian Rose, head of direct donor marketing at NSPCC, said: "This is the most important fundraising campaign of the year for us. It is designed to raise awareness of child abuse, to drive home the message that it absolutely has to stop, and to show every single person in the UK how they can help make it stop."
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