Grobler was one of many Wellingtonians who reported sightings of a pod of orcas on Wellington Harbour on Wednesday, as the beautiful animals put on a show on the capital's shores along Oriental Bay.
The adventure photographer has plenty of experience capturing stunning wildlife shots but says this experience with the orca, while unplanned and unexpected, was "some of [his] best work".
It was truly a chance encounter for Grobler, who'd only thought of getting his camera out because of the sunset.
"I was going out with my mate for an evening freedive out near Moa Pt around about 7pm yesterday. I had taken my camera with me but had left it in the truck, after getting into the water and seeing the beautiful sunset and clear water I quickly realised I need to go back to get my camera," he told the Herald.
"On the way back into the water, I got a big fright as this big thing came up to me. As soon as I realised what it was, I rushed to pull out my camera to capture the moment."
The phographer says he never felt scared as, somehow, he could tell the orca wasn't threatening.
"It was just curious. It swam past me a few time, slowing down and turning to look at me, catching eyes with such a massive creature where it notices you is an surreal experience I will never forget," he says.
"It came within touching distance, and I could see all its battle wounds."
You can see more of Grobler's wildlife and outdoors photography and films on his Instagram and YouTube channel.