Fans of idiosyncratic London theatre will thrill at the news: the King’s Head is back. This much-loved Islington pub venue has had some cosmetic sprucing up — although the new bench seats will still leave you needing an osteopath — but the real renaissance is in the programming. From now on, homegrown productions will receive decent-length runs and confidence is such that scheduling currently runs into 2009. Even the National hasn’t declared itself that far ahead.

The Black and White Ball is an accomplished start to this season. Billed as a “musical mystery”, it elegantly blends a slightly random selection of Cole Porter songs with a freshly-written 1940s society whodunit and has more than enough style to hold things together when the substance starts to flake. A cast of six fine musical theatre performers, plus a golden-haired moppet of a young girl, are an enormous help.

The plot basics are wheeled out in some clumsy initial exposition, which owes more than a passing debt to Sondheim’s Follies. Leah, a writer, returns to the New York ballroom, now awaiting demolition, where the fabulously elegant titular ball was held in 1949, at which toast-of-the-town author Jay St John was murdered. Leah, a child at the time and, it transpires, St John’s step-daughter, is determined to crack the crime once and for all.

Eleven-year-old Leah might have been flabbergasted at the murderer’s identity but we’re certainly not, so the suspense levels aren’t exactly of Agatha Christie proportions. It’s also a struggle to believe that Jay (Chris Ellis-Stanton) is as tortured a soul as writer Warner Brown would have us believe. Nonetheless, Matthew White’s production is so darn elegant that we soon stop quibbling and start smiling.

There’s a smashing central turn, redolent of classy 1940s Hollywood, from Katherine Kingsley as Jay’s ambitious publisher who, with head ruling heart, later becomes his wife. Liza Pulman and Charles Shirvell provide some sassy between-scenes singing and they are joined by Mark McGee’s mysterious drag artist for a priceless, skirt-hoisting Can-Can (“You can can-can too”). An impressively exuberant relaunch.

Until 4 May (020 7226 1916, www.kingsheadtheatre.org)