Harper Lee is to publish her second book - 55 years after To Kill a Mockingbird. But, it was actually written before the 1960s classic.

A manuscript attached with To Kill a Mockingbird's typescript was discovered by Harper Lee's friend and lawyer Tonja Carter last year.

It has been announced the book will now be published, becoming the 88-year-old author's second publication. It is entitled: 'Go Set a Watchman.'

Interestingly, Harper Lee confessed the book was written before To Kill a Mockingbird, and was meant to be her first novel. The author had kept a distance from the press for decades after the success of her first, and then only book. But discovery of a second title has swept the world with fervent cheers.

The new release will feature Scout as an adult who travels from New York to fictional home town, Maycomb, to visit her father, Atticus.

Her publisher stated: 'She (Scout) is forced to grapple with issues both personal and political as she tries to understand her father's attitude toward society, and her own feelings about the place where she was born and spent her childhood.'

Harper was instructed to write To Kill a Mockingbird using material from Go Set a Watchman. Flashback scenes were used as inspiration to build Scout's young character and Lee's first page-turner. It has been 55 years since the author's first book was published. It has sold over 40 million copies and won a Pulitzer in 1961.

Believing, Go Set a Watchman, to be literally lost in the 20th century, upon realisation of the book's existence, the Pulitzer Prize winner didn't feel her earlier 304 page effort was "worthy." But it was met with enthusiastic reviews by a select audience.

"After much thought and hesitation, I shared it with a handful of people I trust and was pleased to hear that they considered it worthy of publication." - Harper Lee

The author is pleased to announce its publication date which is set for 14th July this year, with no revisions to the original manuscript. In the classic tale of To Kill a Mockingbird, Harper's ability to intersperse loveable characters through the central theme of racism in 1930s South America is an eloquent read. The book depicts a combination of endearing characters, narrated through young Scout and (sibling) Jem's eyes. All the while pulling at tense racial strings, ascending like a guitar solo playing out an unnerving period of social exclusion and inequality.

Harper Lee's literary success with her anti-racist read was revered throughout generations, and studied across the world. It made many essential reading book lists was turned into a film, with some still deeming the book a cult classic.

It's expected the new release will mark a brand new era for millions of existing fans, and spark new interest amongst others.

The world gets to witness an unexpected pinnacle moment which has been patiently waiting for the celebrated author. And as there will be no edits, keeping the original material untouched, Harper Lee will present the 21stcentury with a remarkable organic gift. Go Set a Watchman is travelling through time, and being brought back - to the future.