In the third season finale, lead character Hank Moody (Duchovny) was arrested for committing statutory rape.
"We ended up with Hank going to jail so that was the low point," said the actor, in an official interview for Showtime. "This season, we're going to rise up again."
His co-star Madeline Martin (Hank's daughter Becca) added: "This season is about love, loss and [then] carrying on."
Guest stars set to appear in the new season include Zoe Kravitz and former FlashForward star Michael Ealy.
Californication returns on January 9 at 9/8c on Showtime.