Sparks fly between KJ Apa and rumoured girlfriend Britt Robertson in I Still Believe trailer

Fans of Kiwi movie star KJ Apa have been blessed with their first look at his role as Christian rock singer Jeremy Camp in the trailer for I Still Believe. 

The former Shortland Street actor stars opposite Britt Robertson, whom Apa is rumoured to be dating in real life. She plays Jeremy's wife Melissa, who is battling ovarian cancer as the couple plan to marry. 

Apa and Robertson were reportedly seen canoodling at a Comic-Con party last month, but neither has confirmed an off-screen relationship. 

The trailer also shows off Apa's singing abilities as he takes to the stage with guitar in hand. 

Despite coming from a "really musical household," Apa told People he was "terrified" about doing his own singing in the film. 

"I'm super uncomfortable when I sing," he said.

"I went into the studio in Nashville - I did that first before we shot anything - and I think that really gave me perspective on the film. 

"Luckily, it couldn’t have gone better," he added. "I think people are going to love it."

I Still Believe also features country music star Shania Twain, who used to own property in New Zealand with her ex-husband. 

Newshub.