Gibson was born into a devout Christian family in Sydney. He was raised in a strict fundamentalist environment, and by 16 was teaching in a Sunday School run by his parents. At 17, Gibson dropped out of high school to attend Baptist Bible College, but returned to complete high school after one year of study. During this year he published his first short story, aged 18, and won several awards.

After an anomaly in his Higher School Certificate placed Gibson's entire grade in the lowest percentile band in the state, Gibson found work as a laborer while completing his first novel.

Gibson's first novel was acquired by HarperCollins in Sydney in 1994, and released the following December. A gruesome literary thriller titled 'D', the novel sold out the 10,000 copy print run in little over a month.

At a book signing at the Sydney Opera House, Gibson inscribed more than 200 copies of the novel. A number of signed secondhand editions now appear for sale online.

With the publication of 'D' just five weeks after his 22nd birthday, Gibson broke the Guinness World Record for the world's 'youngest novelist writing adult-themed work'. The record was held at that time by Jennifer DiMarco, whose book 'Escape the Wind' was published two years earlier at age 24.

Prior to the publication of his first novel, Gibson won recognition in short story awards and anthologies including 'Paradise To Paranoia' published by University of Queensland Press, Suncorp Literary Awards and commemorative anthology, Young Writer of the Year, and Nescafe Big Break 1994.

Gibson also participated in the judging panel for the Nescafe Big Break for two subsequent years.

Gibson's novel received favourable reviews in numerous periodicals ('Aurealis', 'Australian Newsagent & Stationer', 'The Southern Star') and became a popular item in public libraries through the Australian government's Public Lending Right Scheme.

"Gibson is an accomplished poet and his chapters and literary allusions add some meat for the more erudite readers. Hence, this well written 'pulp' novel could readily catch the eye of your more 'serious' readers. Both groups should enjoy, as they say."...Australian Newsagent & Stationer, Dec 1995/Jan 1996, Page 18, 'It's a D Good Yarn'

Gibson made several media appearances, including national television (‘Good Morning Australia’, and featuring in a 1-hr TV special), appeared in TV commercials ('Nescafe' TVC w/ Russell Crowe), national radio (ABC national radio), print (Sydney Morning Herald 23/12/95, The Australian, Telegraph Mirror 16/12/95), voice-over for pre-recorded radio and other TVCs, and live appearances as a guest on late night television (‘Ground Zero’, Network 10).

Gibson is a member of the high IQ society 'Mensa'.

In 1996 Marcus completed two courses at the Australian Film, TV and Radio School; ‘Focus on Scriptwriting’ and ‘Directing, for Non-Directors’, and participated on the judging panel for the AFTRS Cinematography award.

The same year, he attempted to launch an electronic media publishing venture and secure the inaugural world trademark and patent for the 'eBook', but the applications lapsed after the withdrawal of investors during the October 27, 1997 mini-crash.

In the following years, Gibson travelled extensively, worked as a script editor, and freelance writer while still seeking a publisher for 'The Atheists' Bible'. Drafts of the manuscript circulated in 2001, discussed extensively acts of terrorism attributed to Osama Bin Laden. Gibson withdrew the novel from sale subsequent to the World Trade Center attacks on September 11, 2001. In 2006 Gibson released a free downloadable PDF of 'The Atheists' Bible' on his website, www.theatheistsbible.com.

Gibson now resides in Melbourne, and recently completed his third manuscript, titled 'The Peace Bomb'. The manuscript predicted a nuclear incident in the Mantapsan Mountains in North Korea, the continuation of Iranian President Mahmoud Ahmadinejad's leadership, and a call by the US government for a new nuclear nonproliferation treaty. Within weeks of the submission of the draft to publishers, all three of these predictions took place.

In September 2010, a link to an unlisted YouTube video was leaked via a Facebook friend, showing a teaser/trailer for a novel by Marcus Gibson titled 'The Dead See'. The featured work appears to be similar to - or a retitling of - 'The Atheists' Bible'.