Why does HBO’s adaptation of the hit novel The No. 1 Ladies’ Detective Agency seem so amazing?

Here’s one reason: it offers a nuanced, compelling tale about Africa that doesn’t center on famine, AIDS, violent warlords, child soldiers, genocide or any other heart-tugging tragedy.

Viewers get a vision of Africa through new eyes, re-creating the sweet, quirky tale of Precious Ramotswe — a smart, good-natured woman who turns a small inheritance left her by a departed, doting dad into the only female-owned detective agency in Botswana, in southern Africa. The series premieres with a two-hour movie at 8 p.m Sunday.

Along the way, the premium cable channel thwarts every accepted piece of wisdom about what works on television. Which makes me really want to see this show succeed.

First great move: casting Grammy-winning R&B singer Jill Scott as Ramotswe, a woman of, shall we say, generous proportions who has little in common with the waifs and malnourished women topping most big time TV shows these days.

Fealty to Alexander McCall Smith’s nine novels ensures there’s no attempt to make the cast more acceptable to American audiences by inserting white characters. And the two-hour movie which starts this 13-episode journey tonight is most affecting when distilling the oddball nature of Ramotswe’s corner of Botswana.

Eager to succeed, Scott’s Ramotswe tests the fidelity of a client’s husband by inadvertently picking him up in a bar; later, a car mechanic smitten with her needs help dealing with a dangerous gangster connected to the disappearance of a little boy.

Through it all, Ramotwe’s own cadre of helpers — eccentric secretary Mma Makutsi, mechanic JLB Matekoni and self-assured hairdresser/neighbor B.K. — act as an African Scooby Gang of sorts, helping Ramotwe find missing dogs, wayward crocodiles and fraudulent dentists in the bustling tangle of everyday life in southern Africa.

The project has quite a pedigree: Oscar-winning director Anthony Minghella (The English Patient) helmed tonight’s two-hour movie and executive-produced the series before his death in March 2008. Another

Oscar-winning director Sydney Pollack also served as executive producer before his death last May. Indie movie moguls Bob and Harvey Weinstein also turn up as producers.

Filmed in Botswana, the series has a size and scope few others can match. And at a time when network TV is getting less diverse by the day, it stars a black woman as the lead in a drama series for the first time since, well, ABC’s ill-fated stab at a blaxploitation series, 1974’s Get Christie Love!

Funded as a co-production with the BBC, where the show first aired last year, the series breaks as many rules as the heroine it describes. Small wonder this crusty TV critic was charmed at first sight.

Bet you will be, too. And you could also reward HBO for backing a show that is everything the industry expects to fail on TV nowadays.

*