Octavia Spencer, right, and Viola Davis are shown in a scene from "The Help." (Dale Robinette/AP)

Amid a slew of late-summer duds, “The Help,” based on the best-selling novel about a group of Southern black maids during the civil rights movement, has now spent three weeks at the top.

The weekend’s runner-up, the Helen Mirren-led thriller “The Debt,” grossed $12.6 million from Friday to Monday. Space horror movie “Apollo 18” and “Shark Night 3D,” neither of which screened for review, came in third and fourth place, respectively.