Hong Kong's oldest political satire show will air its final episode Friday evening, against a backdrop of pro-democracy unrest and fears that an incoming anti-subversion law will help Beijing trammel local freedoms.

The swansong show by "Headliner" also comes after the government launched a review of RTHK, the public broadcaster that makes the programme, which has faced accusations from Beijing loyalists of being overly sympathetic to the opposition.

For the last 31 years the irreverent show has sparked government ire with its skits and often rough lampooning of public figures.

Ng Chi-sum (left) and Tsang Chi-ho film the final episode of "Headliner"
Ng Chi-sum (left) and Tsang Chi-ho film the final episode of "Headliner" AFP / Anthony WALLACE

But a recent episode critical of police, following months of pro-democracy protests, has effectively ended the show, after sparking a rebuke from regulators.

Back in February, as the coronavirus first surfaced in Hong Kong, the programme featured a scene showing a police officer jumping out of a rubbish bin to deliver a skit about protective equipment.

At the time, local media had run reports that police had ample supplies of face masks, while residents and health care workers were scrabbling to get their hands on them.

The irreverent show regularly lampoons local public figures
The irreverent show regularly lampoons local public figures AFP / Anthony WALLACE

The show sparked hundreds of complaints, including from the city's police chief, and a probe by the Communications Authority.

Last month the regulator agreed with the complaints, that the skit showed "denigration and insult" towards the police, contained inaccuracies and failed to show a broad range of views.

In a statement, RTHK apologised and said "Headliner" would soon air its last show while it reviewed satirical programming.

That sparked criticism from rights and employee groups, which said it had caved to pressure.

The final episode of "Headliner" will air on Friday
The final episode of "Headliner" will air on Friday AFP / Anthony WALLACE

"'Headliner' is a satire and different audiences will have different reactions, so it's unfair to ask the show to be responsible for everyone's feelings," Gladys Chiu, head of the RTHK Programme Staff Union, said after the decision.

On Wednesday, actors from the show were filming their final episode under hot studio lights.

"I would like to say 'see you again' but how can I tell such a big lie," said Ng Chi-sum, a veteran of the show, who was dressed as a dynastic-era empress to mock Hong Kong's deeply unpopular pro-Beijing leader Carrie Lam.

RTHK has increasingly found itself caught in the crossfire of Hong Kong's intense political polarisation.

Modelled on Britain's BBC, it is a public broadcaster which officially remains editorially independent of the government.

It has long been seen by the city's pro-Beijing camp as biased towards their pro-democracy opponents, a charge the broadcaster denies.

Last month, Lam's government announced it had appointed a task force to "review operations and management of RTHK".

Critics fear the move is an attempt to mould RTHK into something that more closely resembles the heavily censored and relentlessly positive state broadcasters of authoritarian mainland China.