The showrunner previously revealed that the fourth series - subtitled The New World - would be "very dark".
However, he told USA Today: "I sit there in the editing room saying, 'Don't cut that joke! Cut the plot, cut the murder, cut the story, but don't cut the joke'."
He added: "It will always be a cheeky show."
Davies admitted that the plot for the ten-part series was not originally envisioned as a Torchwood storyline.
"[The plot] had been ticking away in my mind for a long while," he explained. "And suddenly I thought, there's a popular show, there's a great story, let's put them together. It felt like it definitely could move forward and become new again."
Torchwood: The New World will air on Starz in the US and on BBC One in the UK.