"We've been mates for a long time and we know each other pretty well. We spark off each other and we want to try and use that."
Garner said he was excited about linking up with his old friend and former political adversary Espiner.
Their contrasting styles would complement one other, he said.
"I might be slightly more abrupt whereas Guyon will strategically tear them apart. We both have our ways of getting to that end point."
He hoped the show would be "different, risky and edgy.
"Live television needs to hold people to account and the public needs to be involved in that process. I want the viewers to feel like they own this programme and I want them involved, which they will be."
Garner wanted the show to be compulsory viewing.
"We want to win. Winning for me will be if the programme has longevity."
TV3 beauty Hayes will move from the 6pm news to join established stars Paula Penfold, Melanie Reid and Sarah Hall on the new current affairs show, which will replace 60 Minutes next March.
New recruit Hayes will be heading to the Antarctica in January to film her first report for the show.
"It's not often that we get to start at the beginning of something and make a new programme," she said.
"It will have all the gravitas of 60 Minutes but it is completely new.
"It really does have the best in the business, from producers to editors and cameramen."
Espiner said TV3's investment in local current affairs was in contrast to TVNZ, whose Sunday programme is likely to alternate between 30 minutes and 60 minutes to accommodate other shows.
"You can't close your shop every second week and expect the customers to keep coming back," Espiner said.
According to a press release, 3rd Degree "will bring a human face to the issues that matter to Kiwis, confronting the people who need to be confronted, probing the secrets that need to be uncovered, and celebrating New Zealanders who are living extraordinary lives".
The format will include long-form current affairs mixed with live interviews and interaction with a live studio audience.
"It's just fantastic to see MediaWorks backing a major new current affairs programme, especially in the current economic climate," said executive producer Terence Taylor.