Universal has dated “Riddick” — the third installment in the Vin Diesel sci-fi series — for a Sept. 6 release date, marking the franchise’s first fall slot. Pic also will be released in Imax.

The film, from writer-director David Twohy, picks up with the title character stranded on a desolate planet, fighting for his life against alien predators.

The first installment, 2000’s “Pitch Black,” bowed in February and earned almost $40 million domestically; the second pic, “The Chronicles of Riddick,” bowed June 2004, grossing $58 million Stateside.

“Riddick” currently has the date to itself, though the following week sees three wide releases — Sony-Screen Gems’ “Battle of the Year,” Lionsgate’s “I, Frankenstein” and Disney’s “The Little Mermaid” 3D re-issue.