The weekly publication is aimed at 12- to 16-year-old girls and is hoping for an average circulation of 100,000. The first issue goes on sale on 30 April, priced 90p.
The Mother television spot, which was directed by Ringan Ledwidge through Harry Nash, features a teenage girl looking for something around her school.
Tension builds until she enters the school assembly hall and explodes, splashing pink gunk all over her classmates.
The enline, "bursting with gossip", reveals that she had been looking for a friend with whom to discuss the contents of Sneak. The accompanying soundtrack features a chant by The Balinese Ketchak.
Media planning and buying is through Rocket. The campaign will run nationally on ITV and satellite channels, radio, flyposters and in teen Emap titles including Smash Hits, Bliss and Elle Girl.
Stephen Palmer, Emap Performance's marketing director, said: "We have an ad that will not only be talked about, but will help to articulate Sneak's streetwise attitude, positioning it away from the saccharine that characterises too many of the magazines in this market and the way they are advertised."