Unlike the previous Hitchhiker's sequels, the title is not a quotation from the first novel, but taken from the third chapter of So Long, and Thanks for All the Fish,[7] where it appears in the following passage: The storm had now definitely abated, and what thunder there was now grumbled over more distant hills, like a man saying 'And another thing...' twenty minutes after admitting he's lost the argument.And Another Thing... starts where Mostly Harmless ends, with Arthur Dent, Ford Prefect, Trillian, and Arthur and Trillian's daughter Random standing inside Club Beta, while the Earth is about to be destroyed by the Vogons.

Meanwhile, Prostetnic Jeltz's son, Constant Mown, is having rather "un-Vogonly" thoughts, including an enjoyment of poetry and sympathy for humans.

Things on Nano are not going as planned, and Hillman is struggling to find his god and keep order among his own populace, as well as trying to control the Magratheans who built the planet.

However, many of the staff abandoned their rich employers and several rival religious groups also settled on the planet, the most prominent of these being the cheese-worshiping Tyromancers, led by Aseed.

Constant Mown disables the Vogon gunner, and uses the argument that their orders are to kill Earthlings and not Nanites (legally two distinct groups, with the latter being taxpaying citizens).

Luckily, Hillman's death is short, as the Heart of Gold medical bay restores him to full health, with only one minor change – he now has hooves rather than feet.

Zaphod sets off with Left Brain to work on his re-election campaign, and Ford has decided to stay behind and sample the best Nano has to offer, so he can write material for the Guide.

Although Colfer spoke of "semi-outrage" at the initial idea of another author contributing to the series, he came to regard the book as "a wonderful opportunity to work with characters I have loved since childhood and give them something of my own voice while holding on to the spirit of Douglas Adams".

[1] Adams' widow, Jane Belson, said that she "could not think of a better person to transport Arthur, Zaphod and Marvin to pastures new" and gave the project her full support.

It was abridged by Penny Leicester, read by Stephen Mangan, with Peter Serafinowicz as the voice of The Guide, and produced by Heather Larmour.

[17] Curtis Silver of Wired also praised the book as a continuation of Adams' story that only suffered slightly from some jokes being too clichéd.

[18] Other positive reviews came from The Times, where Lisa Tuttle described it as "a fine job", and from Euan Ferguson of The Observer, who wrote that "Colfer has pulled off the near-impossible.

Charlie Jane Anders, having read the first half of the book, described it as "more of the same" but without leaving a unique impression of its own, with the humour falling "incredibly flat".