Shadowhunters” fans have been anxiously waiting for the Freeform series to premiere on Jan. 12, and avid readers of the book series will be happy to know that the TV series stays true to the original story.

“We are absolutely starting from the beginning of the books and we stay unbelievably true to the spirit of the books,” exec producer Ed Decter said Saturday at the Television Critics Association press tour, during a panel for the hotly anticipated saga series. “We wanted to have surprises both for the real hardcore fans and then we also want to introduce the viewers who have never been introduced to the world carefully and slowly so that they can get caught up in it like we are.”

Star Katherine McNamara, who plays the lead Clary Fray, explained that the show may not go in exact chronological order of the detailed events that play out in “The Mortal Instruments” books, and that Freeform is taking its own twist on the story to make it uniquely their own. “When you read a book, you have such a personal experience with it,” McNamara said. “I think each one of us has certain elements of those characters, but again, we bring our own thing to the characters.”

Dominic Sherwood, who stars as Jace Wayland, promises that despite subtle differences, fans will be satisfied. “Everything that the fans want, I like to think there’s at least an element of it in season one,” said Sherwood. “Whether it happens in its entirety, or it’s alluded to, or it comes and goes, it’s all there in some shape or form.”

McG, who directed the first episode and serves as exec producer, agrees: “It speaks to the passion that everyone has for the nuances of the books.”

However, top of mind for many passionate fans are the romances and relationships of “Shadowhunters.” To their delight, cast member Matthew Daddario teases, “There won’t be any disappointment for hardcore shippers.”