In the preview, the hunky model said he is "best known" for being the child of Olympic swimming legend Lisa Curry and former Ironman Grant Kenny.
"What I'm most afraid of on the course is being the weak link," the 27-year-old confessed in the promo.
"I'm doing this to try and better myself as a person. To try and see where that wall is for me mentally and physically and seeing if I can get past that wall."
In the clip, a distressed Jett was seen telling directing staff trainer Ant Middleton that he is a life guard.
"You look like a f**king wanker," Ant responded.
The promo also showed the former Dancing With The Stars contestant being challenged in a series of gruelling exercises.
He was seen going up against a female recruit in a brutal boxing bout, ropelling down a rope from a helicopter into a freezing cold lake, getting submerged into a bucket of icy water and abseiling down a cliff face.
An insider revealed earlier this year that Jett is set to pocket around $40,000 should he make it through to the end of the course.
It's unknown if Jett will open up on air about the shocking death of his older sister Jaimi.
Jaimi was 33 when she passed away following a private battle with a long-term illness last September.
In the wake of her death, Jett shared a heartfelt message to his Instagram followers where he hinted at a fraught relationship between himself and Jaimi.
“I may not have been the best brother to you all the time, I know you thought you weren’t being the big sister I needed all the time, but I do know we loved one another unconditionally all the time,” Jett wrote, alongside a throwback photo of the pair.
But despite their differences, Jett said he will forever love and remember his older sister.
“I will love you forever. Rest In peace my beautiful big sister, the world lost one of its treasures yesterday, but heaven gained one. You will be dearly missed by all whose lives you touched.”
Jett will star alongside fellow celebrity recruits Home and Away star Dan Ewing, celebrity chef Manu Feildel, NRL player Sam Burgess, Brynne Edelsten, actress Isabelle Cornish and tennis legend Mark Philippoussis.
Also joining the lineup is Bra Boy Koby Abberton, AFL player Heath Shaw, former politician Emma Husar, singer Bonnie Anderson, songwriter Pete Murray and Olympic legends Alicia Molik, John Steffensen, Jana Pittman and Kerri Pottharst.
Elite ex-Special Forces soldiers Ant Middleton, Mark “Billy” Billingham, Jason “Foxy” Fox, and Ollie Ollerton will all return for the season as the Directing Staff.