Opera purists may wish to look away now. As the baritone (in baboon costume) belts out an aria – "Oh Great Kalahari, Wide Okavango, Oh Africa" – hot summer rains beat on the auditorium's tin roof and its doors are flung open, adding howling dogs and a rumbling goods train to the rousing finale.
This is The Okavango Macbeth, a version of the Shakespearean tragedy set among a troupe of baboons, and the setting is the No 1 Ladies' Opera House – brainchild of Alexander McCall Smith, author of the whimsical Botswana-based detective novels. Milan's La Scala seems a million miles away. Opened in 2008, the converted garage on a snoozy road outside Gaborone has established itself as a tasty cultural chaser to the standard tourist fare of safaris and game lodges.
With seating for just 52 people, including a tiny royal box, and room for piano and guitar rather than full orchestra, the No 1 Ladies' claims to be the world's smallest opera house. Opera glasses are not required, any more than metropolitan airs and graces.
"It's a real taste of Africa," says playwright, actor and director Nicholas Ellenbogen, as we sit under an acacia tree watched by a vervet monkey with spectacularly blue testicles. "You can smell the dust of the bush and sense the sheer physicality of the performers. African opera singers and actors are far more physical than Europeans. They're beautiful to watch."
Naturally, given its name and its founder, the influence of Botswana's finest female detective, Precious Ramotswe, is hard to miss. A frieze of cattle and Nguni hide seat covers reflect the livestock she inherited from her father, while a pair of giant yellow platform shoes capture the style of secretary Grace Makutsi. The opera house's white pick-up is the one used in Anthony Minghella's TV dramatisation of the novels, and McCall Smith wrote the libretto for The Okavango Macbeth, its opening opera.
Evening productions include an alfresco dinner, featuring dishes such as venison with Mma Ramotswe's bean salad or butternut soup. Washed down, of course, with her favourite bush tea.
But the No 1 Ladies' Opera House is far more than a quirky literary offshoot. Botswana has a rich tradition of choral singing and McCall Smith is keen to nurture local talent. His initiative is in good hands. Several productions have involved the acclaimed Theatre for Africa, founded in 1989 by Ellenbogen to kick-start sustainable theatre across the continent. I catch rehearsals of Flamingos of the Makgadikgadi with Gaborone's Showtime Company. The lithe performers imitate herons, frogs and leopards through a mesmerising blend of Brazilian capoeira, ballet and contemporary dance, all set to warm Botswanian harmonies.
The opera house is no place for divas. Cast mingle with audience after shows, something that's unlikely with Plácido Domingo – particularly if he's just portrayed a dung beetle. "My greatest wish is to work abroad," says mime artist Isaac Lebati during a break in rehearsals. "The ultimate would be Broadway or London. I love Mr Bean. He does amazing stuff with his body."
The No 1 Ladies' may help him succeed, because its programme offers much more than just opera. Its current schedule includes dramas and open-air concerts by, among others, the Soweto Children's Violin Orchestra, plus farmers' markets and art exhibitions.
If the extraordinary portrayals of animals whet your appetite for a conventional safari, the opera house is also an ideal spot to embark on a tour of locations from McCall Smith's novels.
The building that is now the opera house was originally a garage almost identical to the Tlokweng Road Speedy Motors of the novels. It occupies the peaceful suburb of Kgale Siding, typical of the gentle, vanishing Gaborone captured by McCall Smith.
A short drive away is Kgale Hill, which dominates the western side of the capital and features in the very first line of the series. Just outside its shadow is Minghella's redundant film set, a cluster of pastel wood facades and billboards advising, "Get Wise, Condomise".
Heading back into the capital, we visit locations pre-dating Gaborone's recent steel and glass expansion. Old Naledi is a district of 1960s squats where Mma Makutsi once lived. It still features blockhouses, standpipes and unsealed roads. Extension Two, where she moves, is a sprawl of cheery, low-level houses swaddling the African Mall. A church has had its noticeboard hijacked by Nando's: Stop in the Name of Peri Peri.
Like the books, this quirky tour offers soft whimsy rather than show-stopping drama. You won't visit the Botswana College of Engineering and Technology on a regular tour, but this is the alma mater of the lazy garage apprentices in The Kalahari Typing School for Men.
After the detective's neat house on Zebra Way (Zebra Drive in the books) we refuel at the Equatorial Coffee Company in Riverview Mall, a haunt of McCall Smith. It's a hit of ultra-modern Gaborone, complete with loud Chinese businessmen on mobiles – the new imperialism. It's a sharp contrast to the colonial echoes of our next stop, the Princess Marina Hospital, where deaths were caused by a cleaner unplugging equipment so she could vacuum.
"Your queen was invited to open it in 1966," says my guide, Lets. "But she was so busy, she sent her auntie, and they named it after her instead. Ha!"
Our penultimate location is Mma Ramotswe's favourite shop, the Botswana Book Centre, where teenagers do "everything except buy something". If sleuthing today, she'd question the formidable Agnes, stationed outside with an ancient sewing machine for on-the-spot alterations. "I'm here every day m'dear," she said, staring at my tatty shorts. "I'll be seeing you soon."
We end in the Main Mall where Precious had tea on the veranda of the President Hotel. Dance music blares over coloured stalls, two traditionally built ladies queue outside Pie City and a preacher thumps his chest underneath a billboard for Conn-Sit Designs: In God We Trust, selling men's and ladies suites (sic), priestly robes and choir uniforms. It's bright, light, happy, infectious, much like the novels – and Mma Ramotswe would feel right at home.
• For opera house information, email no.1operahouse@gmail.com. Africa Insight (+267 316 0180, africainsight.com) offers No 1 Ladies' Detective Agency tours from £42pp. Gaborone's Cresta President hotel (+267 395 3631, crestahosp.co.za) has doubles from £114 B&B. Fly to Gaborone via Johannesburg from £939pp (expedia.co.uk). Further information: Botswanatourism.co.bw
