Beneath the endless gags and joking around, Danny and Michael Philippou are nervous as hell about their debut movie.

The brothers told the ABC their screen test was "very nerve-racking", which might be hard to believe coming from the 29-year-old twins who have a passionate fan base of nearly seven million subscribers to their YouTube channel RackaRacka.

Their stunt-laden videos started with a bang: a spoof called Harry Potter v Star Wars got seven million hits in its first week almost a decade ago and now stands at 33 million views.

It is a journey that has taken them around the world and has occasionally placed them in hot water with the law. 

The pair even ended up in court after they drove a car full of water to an Adelaide bottle shop.

Their flippancy outside court might have frustrated hardened court reporters and some members of the public, but their fans loved it.

Right now, though, they are up for an at-least temporary image remake as they launch their movie directing careers with the horror film Talk To Me.

It is a psychological horror movie based on a group of friends who discover how to conjure spirits using a ceramic embalmed hand.

To make the switch from small screens to the movies, the brothers enlisted Sydney film company Causeway Films.

The pair have a long relationship with the company and had worked with Causeway's co-founder, Samantha Jennings, on the globally-acclaimed horror movie The Babadook.

Her vast experience in the industry has been critical.

"It was awesome to have people like Sam [who] you can trust — [who] has the project's best intentions at heart — to have it be the best film and we just know that we can trust her," Michael said.

Samantha had the task of harnessing the brothers' talents, but said she had not felt the need to rein in their limitless enthusiasm.

"Danny and Michael have a huge amount of energy, but they're also really focused and really serious about filmmaking," she said.

"I think that this is a film that will appeal to RackaRacka's fan base and absolutely deliver on expectations.

"But also I think it exceeds those expectations and will reach a wider audience."

Causeway Films and the Philippou brothers will be feverishly working on Talk To Me until just before it premieres.

However, that will not stop the twins from chasing other opportunities.

"We have, like, 10 to 15 other films that we're working on, films, TV. There's one that we've got pretty close called Bring Her Back," the brothers said, speaking over each other. 

"So, Causeway Films, do you want to do that? I guess we'll see how this one turns out."

Talk To Me will close the Adelaide Film Festival on October 30, at Her Majesty's Theatre.