South Australian man to reveal grief after killing his best mate in a high-speed car crash

South Australian man Nicholas Holbrook was 18 when he was killed by his best mate Phillip in a high-speed crash.

Mr Holbrook died when the car he was a passenger in slammed into a tree on West Lakes Boulevard in the Adelaide suburb of Westlakes in 2009.

The crash was devastating for both the first responders that attended and Mr Holbrook's parents Glynis and Michael.

READ MORE: Three generations of one South Australian family involved in horror double fatal crash

In never-before-seen interviews, they're telling their stories to warn South Australians about the long-term trauma of car crashes.

Phillip, the driver, will also expose the psychological and emotional scars left by the experience of killing his best mate.

SA Police Deputy Commissioner Linda Williams said the interviews warn "that one stupid act on the road can cause life-long damage".

READ MORE: Skydiver seriously injured in coastal Victorian town

"Nobody wants to live with that guilt," Deputy Commissioner Williams said.

Appearing on TV from Sunday, the campaign includes 13 different commercials which will be released gradually to build the story of Mr Holbrook's crash from various perspectives.

The first will be Phillip's account of the moment he learned his driving had caused his best mate's death.

The campaign will also appear on billboards, in shopping centres, online and on social media.

READ MORE: Qantas to roll out digital health pass for international flights

Police Minister Vincent Tarzia said these are "real stories told by real people".

"I can't see a situation where people wouldn't be affected in some way by these heartbreaking stories," Mr Tarzia said.

"Watching this campaign resonated with me on so many levels – as a father-to-be, a son, a brother, a friend."