The brick-tiled pavement glistens in the late afternoon sun. Drizzled over it are lashings of yellow glue.

The unusual scene outside the Central Government Offices in Admiralty is in anticipation of a potentially sticky situation: protesters prying the bricks loose and hurling them at a very important visitor.

Today, China's third-ranking leader Zhang Dejiang - also the man in charge of Hong Kong affairs in Beijing - arrives for a three-day visit that has the Hong Kong government pulling out all the stops. These include unprecedentedly elaborate security measures not seen even when then Chinese President Hu Jintao visited in July 2012.

But then, the past four years have been a tumultuous period for Beijing-Hong Kong relations.

Both sides have needled each other in a vicious circle. There were the Occupy mass movement in 2014, the Mong Kok riot in January and the rise of pro-independence agitators. There were also Beijing's harsh rules on electoral reform, open interference in domestic affairs and the case of missing booksellers likely to have been nabbed by mainland agents.

The visit of Mr Zhang, who heads the National People's Congress, or China's Parliament, and the most senior Beijing leader to visit since Occupy, is meant to reset the troubled relationship, declares a senior Hong Kong adviser to Beijing.

"What China is doing is to turn over a new page in its relationship with Hong Kong," says Professor Lau Siu Kai, vice-chair of the Beijing-backed Chinese Association of Hong Kong and Macau Studies.

He says the central government is readjusting its policies "to seek a better environment in Hong Kong". Instead of tough talk, it has been softening its rhetoric. And today's visit shows that even though Hong Kong lawmakers rejected Beijing's electoral reform proposal, "China is not holding any grudge".

The recalibration in Beijing's strategy is likely a recognition that its hard-line approach had simply alienated the moderates and strengthened the hands of radicals - most notably the young pro-independence activists.

So during his trip, Mr Zhang will meet 10 selected legislators, including moderate pro-democrats, at a 40-minute cocktail reception - a rare meeting. He will deliver a speech at a "One Road One Belt" summit in Wan Chai, where he is expected to elaborate on how Hong Kong can play a role in President Xi Jinping's ambitious project.

He will also "show Beijing's concern" for the well-being of ordinary Hong Kongers.

But there will not be many spontaneous up-close and personal interactions. Some 6,000 police officers are reportedly being deployed daily to ensure Mr Zhang's safety.

Parts of Wan Chai, where he will be staying, is in lockdown mode, with roads closed and 2m-high barricades erected. Construction work in the area has been halted. In taking the measures, the police cited a "high level" of terrorism risk.

On Sunday, Xinhua news agency reported that a Hong Konger was arrested in Shenzhen for buying a drone with the alleged intention of using it to disrupt the visit.

But it will take more than a three- day jaunt to resolve the deep-seated problems in the relationship. Beijing may be willing to change its style but not the substance. Prof Lau says there will be no backtracking on electoral reform.

Some of the more radical pro-democracy legislators have already said they will not be attending a banquet in his honour, while activists decry the draconian security measures, which they say will prevent Mr Zhang from getting the true picture of Hong Kong. The Civil Human Rights Front is calling on people to demonstrate tomorrow.

Still, for some Hong Kongers weary of the incessant warring, Mr Zhang's visit offers a glimmer of hope that there can be a dialogue.

Technical engineer Fung Wai Lung, 36, says: "There is no direction for Hong Kong; we don't know where we are heading.

"With this visit, we hope that there is some sincerity in him wanting to meet the pan-Democrats, and to hear what they have to say."

One message to Beijing will be not to allow unpopular Chief Executive Leung Chun Ying to have a second term. The next election for the city's top post by a small circle of loyalists will take place next March.

Indeed, says Prof Lau, Mr Zhang will be "intensely assessing the situation as to what kind of person is needed (to lead Hong Kong), especially in terms of promoting Hong Kong development and national interests".