Fans of Linda Greenlaw are in for an unexpected treat. Greenlaw recently finished her first nonfiction book in five years; publication is set for spring 2010.

The book, tentatively titled Seaworthy, chronicles the 52-day swordfishing voyage Greenlaw made last fall, in which she returned to the industry after a nine-year absence.

Those anticipating Greenlaw’s third Jane Bunker mystery have an indefinite wait ahead of them. After completing Fisherman’s Bend, she and publisher, Hyperion, came to an agreement releasing Greenlaw from her contractual obligation to write a third work of fiction.

According to Greenlaw, of Isle au Haut, halfway through her work on Fisherman’s Bend the editor she had always worked with at Hyperion quit his job. “I really liked him,” she said, “he had become a good friend.” He continued to work with Greenlaw to finish Fisherman’s Bend, but that was it.

After that, Greenlaw’s literary agent encouraged her to make a move, and she did. Her relationship with Hyperion “ended on a good note,” she said, “I didn’t burn any bridges.” Greenlaw explained, “I enjoy my non-fiction books more than my fiction. That’s not to say I won’t write a third Jane Bunker someday.”

After her release from Hyperion, Greenlaw’s agent was able to get her a new deal with Viking/Penguin for two books of non-fiction. The first of these is Seaworthy. Greenlaw felt that her return to swordfishing was fresh fodder for a non-fiction book, and wanted to “strike while the iron was hot.”

This trip, which began September 16, 2008, made headlines last fall when Greenlaw was arrested for illegally entering and fishing in Canadian waters.  The arrest came at the beginning of the trip, after the first set of the season. Though Greenlaw admitted to being technically guilty of the charge (she crossed the international line accidentally), after a lot of thinking she pleaded not guilty in order to have an opportunity to tell her side of the story in Canadian court. “I wanted to get the facts out,” she said. “There was a lot of misinformation after my arrest.” The boarding of her boat, her arrest and her day in court are detailed in the book.

The second book in the contract, according to Greenlaw, will be a follow-up to The Lobster Chronicles. It will update the reader on changes in the community on Isle au Haut, as well as in Greenlaw’s personal life. Most notably, Greenlaw will write of how she recently became the legal guardian to a 17-year-old girl, and all the changes that come with parenting a teenager. When pressed for details, Greenlaw demurred, because “I want to save it for the book.”

In a separate contract, Greenlaw will also write a second cookbook with her mother, Martha Greenlaw.

Linda Greenlaw returned to swordfishing as part of Discovery Channel’s latest documentary series “Swords: Life on the Line” which premiered August 11. “Swords” is a “Deadliest Catch”-style show that follows several swordfishing boats and their crews through the 2008 swordfish season.

The series premiere highlighted Greenlaw and the trouble she and her crew had with their boat, Sea Hawk, before they even reached the fishing grounds.  The show earned high Nielsen ratings, ranking second among primetime ad-supported cable telecasts, and number 11 among all networks, surpassing several primetime broadcast programs, including ABC’s “Better Off Ted” and CBS’s “Medium,” according to tvbythenumbers.com.

The show was produced by Original Productions, which had a tentative deal with NBC. After that deal fell through, it was uncertain whether the show would ever make it to the air. Eventually Discovery Channel picked it up. Producers had little communication with Greenlaw for months after taping ended, so it came as a bit of a surprise when she was told the premiere date early this summer. She says she was pleased with the end result. “I thought they did a good job keeping the tension,” she said. “I was on the trip and I know what happened, and I was still nervous. It was sort of exciting.”

There is already speculation about whether there will be a second season of “Swords,” and consequently another fishing season for Greenlaw. “I am hoping to know that very soon,” she said, as swordfishing season begins in September. Though, as Greenlaw noted, “It depends if Discovery wants to do season two. And then do they want Linda Greenlaw? I have been hearing things, but not from the right people.” Greenlaw was absolutely clear on one point. If there is a second season of “Swords” in her future, “I’m not going in that boat,” she said. “I want a better boat.”