Nicolas Cage whipped out some unexpected improvised singing for his latest mind-boggling thriller film, now in cinemas.

Lorcan Finnegan’s feverish drama The Surfer releases today (Friday, 9th May) and stars Cage as an unnamed man who returns to his birthplace in Australia to buy back his childhood home.

When he tries to surf the local beach with his son (played by Finn Little), a group of aggressive locals, led by Scally (Julian McMahon), turn them away from the waves.

Left with no choice but to stay in his car awaiting a call from his real estate agent, Cage’s eponymous surfer becomes increasingly disturbed as Scally’s gang continues to cruelly torment him.

At one point in the film, when the surfer is at his breaking point, Cage was left to improvise his rambling dialogue.

Speaking exclusively to Express Online, director Finnegan recalled: “In the script process he just had tweaks to his dialogue, how he’d like to say certain things or reverse information around or delete bits. So that was all fine.

“Once we got shooting, in terms of improvisation… he’s very prepared.

“Once we got on set, Nic never needed his script ever. He knew all his dialogue. Which allowed room for trying different things.”

Cage is undoubtedly one of the most prolific and dedicated actors in Hollywood and has seen a resurgence in recent years with other equally disturbed and inventive thrillers.

In the past decade he’s pushed himself to the limit with films like Mandy, Color Out of Space, Pig and Longlegs, just to name a few.

However, The Surfer takes the star to a whole new level of madness with Finnegan’s Franz Kafka-inspired descent into barbarism and drug-fuelled toxic masculinity.

The director continued: “There’s a scene where he’s walking around the car park with no shoes on, blood on his foot and totally dehydrated and delirious.

“I think in the script it said he’s asking people, ‘Have you seen my broker?’ and mumbling incoherently and that was it.

“Once we were shooting it we shot on an 8mm lens, it was very wide, you could see everything. All the crew and everything had to hide inside the cars in the car park.”

Recalling Cage’s on-the-spot creativity, Finnegan added: “And he just went off on one! Talking about wanting to make his wife dinner on the balcony and cook her clams with pasta.

“And that went on for longer than what’s in the movie. He started singing Jump Around by House of Pain and started jumping around with the three young kids.

“That didn’t make the cut, but it was great. It will be on the Blu-Ray bonus stuff.”

Unfortunately, film fans won’t get to see Cage performing the classic ‘90s track, but there are plenty more mind-melting moments to expect from this thriller unlike any other.

The Surfer is in cinemas now.