There's plenty of spectacle, from the giant White Knight Messenger puppet travelling up and down St Kilda Road like an angelic Transformer, to giant inflatable rabbits lolling on the Alexandra Gardens lawn and mesmerising  projections at the State Library causing lengthy queues.

But even with the return of projections on Flinders Street, there seems less to see and fewer works of public art that are as truly engaging as in the first four years of the event.

Birrarung Marr and across the Yarra are good places to grab a bite to eat or escape the giant crowds and rush of selfie-takers, but on the other hand there is much less to see and do.

Further north, however, the Carlton Gardens have come alive with installations that have both mesmerised and terrified children.

Here's what's happening around town as the evening unfolds.

National Gallery of Victoria

The National Gallery of Victoria has previously staged special installations for White Night but this year is notably quieter with no works inside the gallery curated especially for the evening.

Projections on the St Kilda Road building's exterior have been a highlight of White Night in previous years, featuring artists including Ballarat's Josh Muir in 2016.

Just before 9pm there was a brief blast of projection outside NGV International, fittingly a wall of water cascading down the brutalist walls.

The centerpiece next door outside Arts Centre Melbourne is a lilypad that looks suspiciously like those that floated on the Yarra for White Night several years ago - recycling, it seems.

Alexandra Gardens

The giant inflatable bunnies and illuminated flowers proved popular in Alexandra Gardens, drawing thousands to the lawn.

But as static installations they provide little or no opportunity for interaction, apart from the odd child jumping on the rabbits or people standing in front of them for selfies.

Further into the gardens a hovering sound and light sculpture caked The Medusa, modelled after a species of freshwater jellyfish found in Victorian rivers, proved more interesting.

A group of people sat under the installation - by Melbourne creative studio John Fish - which was hoisted in the air with a small crane, as its colours changed and it emitted a changing soundscape.

While the southern sector is traditionally less congested, by 9.30pm even the foot traffic over the Princess Bridge was flowing much more freely than in other years.

Carlton Gardens

Families are out in full force at Carlton Gardens as the dusk grows darker and the lights of White Night grow stronger.

People flock to the Sonic Light Bubble at the southern end like moths to a porchlight.

It resembles a giant, partially submerged clear beach ball, dotted with discs of coloured light. It responds as people touch it, emanating strange noises and changing hues, pulsating.

The children are fascinated by this, but away from the bubble, other kids seem a little freaked out by the 40 fake possums hidden in the treetops - their eyes glowing red.

Of course there are plenty of real possums scurrying around up there too, and the screech of bats can be heard even over the soundtrack to the projections at the Royal Exhibition Building. 
 

Royal Exhibition Building

If you're terrified of spiders or clowns, probably best to steer clear of the projections at the Royal Exhibiting Building. If you're a Tim Burton fan however, scoot over here pronto.

Rhythms of the Night begins with a domestic soundscape: a telephone ringing, a dog barking, car doors closing, a baby in its crib, someone snoring. Weird clocks in deep blues and reds, with giant eyeballs instead of faces, adorn the facade.

The clocks tick down to zero and a nightmarish, Wonka-esque figure flicks a switch and draws us into his psychedelic steampunk wonderland.

Striped hands massage the edifice, wind up toys spin, whales swim through bright red liquid. The highlight is when the building is transformed into one made entirely of skeletons and cobwebs, crawling with giant purple and green spiders.

There's a spectacular technicolour finish with leaping bodies, a celestial bear and a powerful owl, and a pacey soundtrack worthy of a Hollywood epic.

The whole performance goes for about 20 minutes and the crowds love it - they break into applause every time.

There are also a couple of things happening in the square between the Royal Exhibition Building and the Museum.

Nebulous is a spherical sculpture lit up from below against the black sky. It's reminiscent of a Chinese luck charm, with its red wiry fronds covered in gold and silver discs that look like coins fluttering in the wind.

It gently rolls in and out of itself, controlled by a slow piston, like lungs expanding and contacting. Mesmerising. 

Then, there are these strange creatures on stilts.

State Library

At the State Library, the protest against the Lord Mayor's homeless ba is heating up against an impressive White Night backdrop.

Chanting "homelessness is not a crime" and "shame on you Robert Doyle", about 30 people are now involved and the protest is drawing a small crowd thanks to a lighting projection sign, which has illuminated the words "homeless ban".

While the protesters are dwarfed by the massive crowd lining up to see the free light projections at the State Library, more and more people are stopping by the protest - meaning the organisers are definitely getting their point across.

Inside the library, meanwhile, the walls have come alive with sea creatures.

The "sea dragon's lair" was worth the hour-long wait for many people, some appeared to have come into the city only for the library's projection.

Meditative and calming in contrast to what was outside, a city is projected on the walls, which then becomes swollen by the ocean - making way for the majestic sea creatures.

It certainly feels like a you are inside a warm, cosy lair.

Swing City

It's a great vibe down at Swing City, according to reporter Hannah Francis. The music and dancing kicked off just before 8pm.

Red, black and white seem to be the colours of choice for the well dressed dancers taking part in the dance marathon.

Let's hope there is some La La Land style dancing across the bonnets of the vintage cars later tonight. 

Birrarung Marr

This time last year there were a feast of projections visible across the Yarra from Alexandra Gardens.

This year, however, there's very little to look at here, apart from the world music stage across the Yarra and the odd canoe or party boat on the river.

It's a good spot to come though if you're hungry - there's a queue of food trucks serving sliders and burgers, Indian, German and Portuguese meals as well as coffees and desserts for those who need sustenance to keep them going until dawn.

The whole experience south of the river is much more leisurely than at any other White Night.

If the main aim of organisers was to simultaneously slow things down and keep things moving, they've done it here. Although it does come at a price - there's less to see and do too.

Little Lonsdale Street and QV

Melbourne's weather was especially erratic this evening - it only rained over Little Lonsdale Street.

A haze of purple light and sprinkles of water covered dozens of people, for the annual White Night "Purple Rain" event.

Those who participated seemed less than enthused with an obvious lack of Prince playing over the soundtrack.

Meanwhile, in the middle of QV shopping centre, three angels stand inside a bright square box as part of the "Enlighten" exhibition.

The angels dance about to the theatrical music, posing to a gathering audience.

A basket carrying pen and paper was dropped via fishing rod into a crowd of children, with the audience invited to write down their hopes and dreams and pass it back to the angels in a box.

Eventually a young girl carrying a single white balloon was encouraged to place the tiny notes into a bag. The balloon was then set free, with the crowd cheering and a lot of exited children watching it sail high above QV and into the night sky.

White Night budget still a secret

White Night Melbourne delivered $16 million to the Victorian economy in 2016 and should contribute at least as much again in 2017, Victoria's Creative Industries Minister Martin Foley has revealed.

The budget for the event, now in its fifth year, is still under wraps. But the $16 million figure at least provides a sense of the economic benefit to the state of the dusk til dawn cultural festival, which attracted more than 550,000 people to the city in 2016.

Asked about the future of the event, Mr Foley said the state government would make that decision after White Night Melbourne, and its debut in regional Victoria, White Night Ballarat on March 4, had ended. He did however allude to the possibility of it continuing into 2018 and even 2019, and potentially open up for tender again to other regional centres in later years.

The first few hours of the event appeared to run smoothly, with a steady stream of revellers heading into the city seeming to heed advice from organisers to help ease crowd congestion and keep foot traffic flowing.

Speaking several hours into the event, at a VIP function at the National Gallery of Victoria, new artistic director David Atkins said things appeared to be running smoothly - with the biggest challenge for organisers being traffic flow.

"Here the audience is part of the show," he said.

How to get around

For those planning to head into the city tonight (or, alternatively, hoping to avoid any disruption from White Night), here's a handy list of road closures, public transport information and suggestions on how to get home.

It's worth printing out the official map before you leave home, as it can be difficult to access the official website once mobile phone networks and public wifi become jammed due to the huge influx of up to 600,000 people into the city.

Organisers have issued some tips too for the best way to navigate White Night Melbourne, as well as where to eat and drink.

"My pick would be to start your journey up at Carlton Gardens, then come down into the city," Atkins told arts reporter Annabel Ross.

"We've got more than double the normal installations in Carlton Gardens – from three to seven – and they're fairly substantial installations."

The smartest way to arrive by train is to jump off at Melbourne Central and head towards the top end of the city, then make your way back down towards the National Gallery of Victoria.

"Certainly I wouldn't try to get off at Flinders Street," says Atkins. "A really good way to do it is walking down the hill [from Carlton Gardens] to get to the south [Alexandra Gardens] and then head back into the city."

Weather report

You might need to rug-up but should be able to forego packing a raincoat, according to forecasters.

Rain showers forecast for Saturday are expected to clear in time for the festival that kicks off at 7pm.

Any light rainfall on Saturday afternoon was expected to ease before 9pm, Bureau of Meteorology senior forecaster Scott Williams told reporter Alexandra Laskie on Saturday.

He said the best time to venture out into the CBD was between 10pm and midnight.

What to see

Trying to figure out what to see? We've done the legwork for you:

• Rebel Elders: A series of cinematic vignettes depicting senior citizens in various states of triumph and inspiration will be projected on the walls of Rainbow Alley, just behind Swanston Street off Little Collins.
• Medusa: A light and sound sculpture that will hang from the trees in Alexandra Gardens, casting a glow over the lawn as her five-metre long tentacles swing in the breeze.
• Music stages: The Bourke Street Mall Live Music Marathon stage will feature pop and rock-skewed artists including Fem Belling, a singer and former leading lady on London's West End and The Cat Empire frontman Felix Riebl​. There are four other music stages: The World – Live stage at Birrarung Marr featuring the Lehenda Ukrainian Dance Company and The Tek Tek Ensemble; the mixed bag The Major Chord stage at Federation Square; the Unplugged stage at M Pavilion, home to a selection of chillout acts; and three Buskers Pitches across the White Night precinct with all-night performances from local buskers.