Comcast Corp. and SonyPictures Entertainment will unveil a new horror and thriller network this Halloween through video-on-demand, the first collaboration between the two companies under a deal to create new cable channels.

The as-yet-unnamed channel, to be announced Monday at National Cable & Television Association's annual The National Show conference in Atlanta, will feature over 1,000 horror and thriller movies and TV shows from the Sony/MGM libraries including "Silence of the Lambs," "I Know What You Did Last Summer," and "Panic Room."

The channel, to be offered free to digital subscribers, will feature at least 20 films and some TV series, comprising 40 to 70-plus hours of programming. A quarter of the content will be changed every two weeks.

The channel will be supported by advertising targeting the highly desirable youth-to-young-professional market. Ad revenue will be shared by Comcast and Sony Pictures of Culver City, Calif.

"It really appeals very strongly to a fan base of 18- to 34-year-olds," said Diane Robina, president of emerging networks at Philadelphia-based Comcast. "When you're looking at a platform like this, you want to appeal to a passionate and loyal audience."

The two companies said the cable channel will be the first dedicated to the horror and thriller genre. Comcast, the nation's largest cable operator with more than 21 million customers, said 20 percent of feature films released by major studios in 2005 were part of the genre. A third of those movies topped the box office on their debut.

Comcast made a decision to offer the channel through video-on-demand to keep subscribers from switching to satellite TV, which cannot duplicate the service. With the on-demand service, digital subscribers can watch a library of films, TV shows and other content whenever they want.

While Comcast has developed other channels exclusively for the on-demand service, such as ExerciseTV, subscribers prefer to watch movies and TV shows of premium channels such as HBO and Cinemax. Officials say that's how cable can keep customers from jumping ship. Other programs, they say, are helpful, but not dealmakers.

"The real glue is premium on-demand," said Bruce Leichtman, president of the Leichtman Research Group in Durham, N.H. "Nearly half of all viewing is movies and series."

However, cable companies still face the challenge of getting Hollywood content more quickly after it is released. Comcast and Sony said the new channel will not shorten the window for delivery.

The new network will be supported by online content including exclusive outtakes, music downloads and behind-the-scenes footage. Comcast later plans to add a wireless dimension, offering horror ring-tones, sound effects and other mobile features.

The new channel is one of several expected under a 2004 Comcast-Sony agreement, which called for the creation of new cable channels using Sony and MGM content and cemented a distribution deal. The Sony and MGM libraries comprise 7,500 movies and 150,000 TV episodes.

The agreement came in the same month that Sony Corp. led a group to acquire Metro-Goldwyn-Mayer Inc. for nearly $5 billion, including debt. Comcast was part of the group, investing $300 million.