BRITANNIA certainly waives the rules with this gender-bending tale of jolly jack tars and saucy young salts.

Director Sasha Regan firmly focuses her sextant on this sea battle of the sexes despite the fact that these sailors appear to have a boy in every port rather than the usual motley crew of dockside doxies.

Don’t expect a fine array of Technicolor clothing with this one. The togs worn by this all-male cast are distinctly one-tone, most of the costume changes taking the form of underpants on, underpants off. Or that’s how it seemed five rows in from the quarter deck, anyway.

As the late Kenny Everett might have observed, it’s all done in the best possible taste, even if the unrelenting campness does occasionally appear a tad below the plimsoll line.

Gilbert and Sullivan were quite anarchic when you come to think about it, unashamedly poking fun at Victorian pomposity, and in this case firing well-primed broadsides at social conventions, particularly the prevailing caste system of the late 19th century.

But shiver me timbers, heavens knows what some of the more staid G and S traditionalists thought on this opening night.

However, never mind that – just how did some of these strapping lady men sustain that castrati-pitch falsetto? All right, we’re back in the tight underpants department again, and Ben Irish as Josephine most surely led the way, maintaining a rum decanter-shattering vibrato throughout.

No wonder then that the object of his/her affections swept matelot Ralph (Tom Senior) from poop deck to focsle via the mizzen mast with plenty of yo-ho-ho in between.

And not to be outdone we have Buttercup (David McKechnie) who flounces about with gay abandon, the entire crew quite obviously liking the cut of his jib.

But back to jaunty Josephine. She may only be the captain’s daughter, but is she hiding something? To be sure, Captain Corcoran (Neil Moors) appears to be fully in control at the helm, but there’s no doubt that stormy waters most surely lie ahead.

This very modern take on a celebrated comic opera classic moves along like a tea clipper riding the Roaring Forties - and so my advice me hearties is to weigh anchor and set sail for Malvern without delay.

HMS Pinafore runs until Saturday (July 9).