Inspired by the scandalous story of Dido Elizabeth Belle (Gugu Mbatha-Raw), the illegitimate, mixed race daughter of Admiral Sir John Lindsay (Matthew Goode), who was raised by her aristocratic great-uncle, William Murray aka Lord Mansfield (Tom Wilkinson) and his wife (Emily Watson), this is a period drama, complete with heaving bodices and stiff, courtly manners.

Given the dearth of known biographical facts about Dido Elizabeth Belle, screenwriter Misan Sagay has drawn upon inferences from a portrait that was painted of Dido and her half-cousin, Lady Elizabeth Murray (Sarah Gordon), who were raised as sisters on the lavish Mansfield estate. From 1779 to 1922, the painting hung in Kenwood House on the northern edge of Hampstead Heath in London and is now part of the Scone Palace collection in Scotland.

Indulged in luxuries, these two young women were brought up almost as equals, sharing joys and sorrows, until it came time for them to marry. While Elizabeth is groomed for her presentation to society and courtship, Dido is not, although her father left her a considerable fortune. Propriety dictates that marriage is all about status and social standing. Dithering around them are ambitious Lady Ashford (Miranda Richardson) and her two eligible sons: Oliver (James Norton) and James (Tom Felton aka Draco Malfoy). Then there's the vicar's son, John Daviner (Sam Reid), an avid abolitionist. His presence is most irksome since, as chief justice of England, Lord Mansfield is currently deliberating a case known as the Zong Massacre of 1781, an incident of fraud in which 142 sick-and-dying African slaves were drowned so that the ship's owners could claim insurance for their damaged cargo.

Director Amma Asante ("A Way of Life") errs on the side of dignity and restraint, casting radiant British/South African actress Ebatha-Raw in the title role but giving her only Jane Austen leftovers to work with. Humor is lacking, along with subtlety, since every emotional outburst is anticipated in advance.

On the Granger Movie Gauge of 1 to 10, "Belle" is a sumptuous 6. Too bad it's a bit stultifying.