Man, maybe the studios are on to something by not showing us their films... the new supernatural thriller The Covenant conjured up the lead at a sluggish weekend boxoffice in North America with the lowest sales for a No. 1 movie in three years, according to the Hollywood Reporter. The Sony Corp. release sold $9 million worth of tickets in the three days beginning Sept. 8, followed by another new film, "Hollywoodland," with $6 million and previous champ "Invincible" with $5.8 million. The last movie to open at No. 1 with less than $10 million was the David Spade comedy "Dickie Roberts: Former Child Star" with $6.7 million exactly three years ago.