In Queen Of Oz, Catherine Tate plays a spoiled party-girl Royal packed off to Australia to avoid being an embarrassment at home and to try to stave of republican sentiment down under by giving them their very own monarch.

What just took a sentence to explain is padded out over the tediously paced half-hour of tonight’s opening episode, which – aside from the incident which finally got her expelled from the UK, turning up drunk to a school – is virtually laugh-free.

The very premise of the show is, of course, fundamentally flawed, as sending a useless entitled brat to Australia is unlikely to endear anyone to the idea of a hereditary head of state. That wouldn’t matter if it was funny enough, but spending time in Princess Georgie’s appalling company is as much a trial on TV as it would be in real life.

Tate doesn’t write likeable characters. That mightn’t have been an issue in her sketch comedy heyday, but when we’re asked to spend hours in the company of an awful character rather than two minutes, it’s an exponentially bigger ask. 

Georgie doesn’t have any redeeming features. She’s not abominable in the gloriously over-the-top way of a Malcolm Tucker, nor driven to bad behaviour by a misplaced ambition, à la Basil Fawlty. She’s just an entitled, obnoxious, posho being awful to people, usually her staff.

‘Team Queen? Team Shit! That’s what you all are, Team Shit,’ she rages charmlessly at them after one snafu. That’s the level of elegance in the writing in a lazy script that has ‘will this do?’ written all over it.  

Oddly, Princess Georgie occasionally shows an inexplicable ability to be good at her job, in arbitrary contrast to her usual traits. Once in Australia, for example, she ad-libs a speech that endears her to the assembled dignitaries. 

That scene is probably placed there to foreshadow her doing the impossible and turning public opinion around in future episodes, as a dramatic arc would require. But few viewers will surely have the patience to stick around for six episodes of a rude woman shouting.

Certainly, foreshadowing is usually heavy-handed. The moment that much is made of a elaborate floral display, you know it’ll be carelessly destroyed.

Some of the supporting cast put in a game effort, but sympathies go out them for being hitched to such a limp excuse for a comedy which – after the Nan movie and Netflix series Hard Cell – completes a hat-trick of Catherine Tate comedy flops. Still, she's good in Doctor Who... 

• Queen Of Oz is on BBC One at 9.30pm tonight. All episodes are on iPlayer now.