One of the reasons the project took so long to get off the ground was the difficulty Oprah had in convincing a director that she could shed her TV persona and play the central role of an escaped slave in 1870s Ohio - even though her first film outing, in The Color Purple, won her an Oscar nomination.

Sethe with her daughter, Denver (Kimberly Elise)

So it's nothing short of a triumph that one of the world's best-known women is so completely unrecognisable - after a few moments of mental set-adjustment by the viewer - in the character of Sethe.

Based on the true story of Margaret Garner, it's a complex, sometimes harrowing tale that shifts back and forth in time, and mixes the supernatural and the poetic with vivid flashbacks to the horrors of Sethe's time as a slave on the Kentucky farm "Sweet Home" and her subsequent escape over the river to Ohio.

Although physically free, Sethe and her teenage daughter Denver are haunted by the past - their new home literally shakes, groans and glows red with the presence of Sethe's dead baby.

The arrival of an old friend, one of the Sweet Home men, Paul D (the excellent Danny Glover) ushers in a temporary calm, in which Sethe dares to believe in the possibility of love, trust and a future. But the semblance of harmony is shattered when a strange young woman, half-child, half-feral beast, turns up on the doorstep and gradually becomes part of the family.

Sethe and Paul D (Danny Glover), both former slaves from Sweet Home Plantation

Played by British actress Thandie Newton, the part of Beloved is as tricky a role as a rising star might hope for, requiring a mixture of beguiling pathos and fierce malevolence. Newton's extraordinary beauty helps her carry it off. Winfrey, meanwhile gives an admirably restrained performance as Sethe, suppressing her natural exuberance for the part of a woman whose feelings have been numbed by trauma.

In a risky narrative move, the last third of the film is almost entirely given over to the character of Denver (Kimberly Elise) as she slowly gains the courage to liberate herself from her mother's pain and find her own way in the world. Her story provides the crucial arc of the film, and its ultimately uplifting conclusion.

In exploring the legacy of slavery, rather than dwelling on its brutal actuality, Beloved manages to avoid the pitfalls which have dogged previous films black historical films - such the Color Purple and Amistad - being neither sentimental nor a worthy-but-dull morality tale.

Lushly filmed by Oscar-winning director Jonathan Demme - with his favourite director of photography Tak Fujimoto - there's no getting away from the fact that it's nearly three hours long. But it's a rewarding journey through pain, redemption and hope.
Lucie Maguire