Sony's Michael Jackson documentary "This Is It" moonwalked to a stellar $7.4 million in estimated first-day boxoffice on Wednesday.

Pre-release forecasts projected that the pic should open north of $40 million through Sunday. "This Is It" bowed simultaneously in 97 foreign territories, with Sony promoting releases as a two-week-only theatrical campaign.

That could change if word of mouth sustains the early big grosses following solid early support from critics. But for now, the limited theatrical window seems to be stoking must-see interest in the film.

Rival studios were the first to estimate the pic's first-day boxoffice. Sony is expected to release its own number sometime Thursday.

The first-day haul for "This Is It" easily topped daily boxoffice rankings, though it set no records. Paramount's supernatural thriller "Paranormal Activity" was second among all Wednesday grosser with $1.5 million and a $66.6 million cume, while Overture Films' crime thriller "Law Abiding Citizen" ranked third with $880,000 for a $43.1 million cume.

Sony unspooled "This Is It" at 9 p.m. PDT Tuesday, but the studio will include those grosses - totaling $2.2 million -- in its Wednesday tally. Sony acquired worldwide distribution rights for a reported $60 million.

"This Is It" contains rehearsal footage, interviews and back-stage scenes from preparations for what would have been the late singer's lengthy concert series in London.