The literary world is ablaze with anticipation, jubilation and an errant bit of scepticism this morning, awakening to the incredible news that reclusive author Harper Lee will finally publish a follow-up to her famous To Kill A Mockingbird, 55 years following the publication of her debut novel.

Apparently written before the Pulitzer Prize-winning, 40 million copies-plus bestseller To Kill A Mockingbird was published in 1960, the new novel, Go Set a Watchman, features Scout Finch as a grown woman, now living and working in New York, returning to Maycomb to visit her father, Atticus, and encountering many of the much-loved characters who have been seared into the collective consciousness of book lovers worldwide.

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Written in the mid 1950s in the heated heart of the US civil rights movement, Go Set a Watchman is said to contain flashbacks of Scout’s childhood. Lee’s editor at the time was said to be enamoured with the childhood segments and convinced Lee to put Go Set a Watchman aside in favour of the To Kill A Mockingbird storyline set 20 years earlier.

Harper Lee in 1963. Photo: AAP

One of America, and the world’s, most-loved novels, To Kill A Mockingbird is a tale of redemption set in the Deep South during the fraught racial relations of 1930s segregation. Widower and lawyer Atticus raises his two children, tomboy Scout and her big brother, Jem, with the help of black maid Calpurnia. In a fraught court case, Atticus defends the innocence of Tom Robinson, a black man accused of raping a white woman, while the children, along with visiting friend Dill, embark on a quest to draw out reclusive neighbour Boo Radley.

Growing up in Monroeville, Alabama, Lee lived next door to Breakfast At Tiffany’s author Truman Capote’s cousins on South Alabama Avenue, and the pair were firm childhood friends long before either went on to literary stardom. Capote later insisted that the character of Dill is modelled after himself. There have been conspiracy theories suggesting that Capote actually penned the novel, hence why Lee never followed it up, but this has been debunked.

Robert Duvall and Mary Badham as Boo Radley and Scout Finch in To Kill A Mockingbird. Photo: AAP

An immediate bestseller, fans have clamoured for more from Lee ever since she released the book. However, much like Boo, she has remained hidden from the public gaze and has not published any further fictional work, despite initially claiming: “all I want to be is the Jane Austen of south Alabama.” A second attempt, entitled The Long Goodbye, was abandoned, as was one focusing on local murder case during the 1980s.

Literary agents have long known there was another manuscript, but assumed it was an earlier draft of Mockingbird. Go Set a Watchman was apparently discovered by Harper’s close friend and lawyer Tonja Carter, attached to the back of an original typescript of Mockingbird held in storage.

There has been persistent controversy surrounding the nature of Lee’s relationship with Carter, and there are questions being raised already regarding whether or not Lee knowingly gave her consent to publish. Now profoundly deaf and also blind, following a stroke in 2007, the author lives in an assisted care home in Monroeville. Her estate and privacy were long guarded by her sister, Alice, who died at age 103 in November, 2014.

The New York Times reported that all communications about the new manuscript, discovered around the time of Alice’s death, came through Carter.

Harper Collins publisher Jonathan Burnham was reported as saying he was “completely confident” Lee understood and approved of the deal, and that speaking directly with her directly “wasn’t necessary”.

Go Set a Watchman will be released mid year 2015.