Stephen King's latest film knocked 'em dead, so to speak, as "Pet Sematary" earned $12 million in its first weekend, setting a record for the biggest opening ever during the time between New Year's Day and Memorial Day, traditionally one of the year's slowest moviegoing periods.

The film adaptation of King's biggest-selling novel earned a whopping $7,600 per screen in 1,585 theaters.The film, a moderate-budget production with no name stars, opened Friday, April 21, with no advance screenings for critics and therefore no advance reviews anywhere in the country. If there was any doubt about Stephen King's ability to bring in audiences by his name alone it was put to rest once and for all.

"Major League," "Say Anything," "The Dream Team," "Rain Man" and "She's Out of Control" held onto the next five slots solidly.

New to this week's box office rundown were "Red Scorpion," which earned a disappointing $1,640 per screen in 1,268 theaters; "See You in the Morning," which took in a respectable $2,466 per screen in 743 theaters; and "Speed Zone," a flop with $1,235 per screen in 1,195 theaters.

Here's the latest national "top 10" countdown, according to show business trade papers:

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1. PET SEMATARY, $12 million (first week).

2. Major League, $5 million ($251/2 million, three weeks).

3. Say Anything, $4 million ($9 million, two weeks).

4. The Dream Team, $3 million ($16 million, three weeks).

5. Rain Man, $2 1/2 million ($1551/2 million, 19 weeks).

6. She's Out of Control $2 million ($7 million, two weeks).

7. Red Scorpion, $2 million (first week).

8. See You in the Morning, $2 million (first week).

9. Disorganized Crime, $11/2 million ($5 1/2 million, two weeks).

10. Speed Zone, $11/2 million (first week).