The perennially controversial marriage of Tom Cruise and Katie Holmes is over. From the now legendary couch-jumping incident on The Oprah Winfrey Show, to last week's speedily made settlement, it's been a five-and-a-half year rollercoaster. Now we, the watching public, are left with only our memories and so many unanswered questions. Chief among them: did Cruise's unwavering dedication to the Church of Scientology really cleave the couple apart? And what do Scientologists believe, anyway? As ever, bookshelves hold the answers that we seek.
• When trying to understand this mysterious organisation, it only seems fair to let its founder, L Ron Hubbard, have the first word. Turn, then, to Dianetics (New Era Publications, Dh74), the self-help treatise that Hubbard published in 1950. Hubbard urged readers to free themselves of neuroses and achieve a mental state called "clear" by confessing their innermost secrets to "auditors".
• The medical profession was not impressed, and Hubbard's followers were arrested for practising medicine without a licence. Read the academic Hugh B Urban's The Church of Scientology: The History of a New Religion (Princeton University Press, Dh107) - widely regarded as the best impartial history - to learn how Hubbard responded to this rejection by declaring himself the founder of a new religion.
• So what do Scientologists really believe? Access to core beliefs was for years the preserve of the organisation's elite, but high-level defectors have revealed that so-called "advanced technology" documents tell the story of Xenu, a galactic warlord who came to Earth 75 million years ago. See Inside Scientology (Mariner Books, Dh57) by the Rolling Stone journalist Janet Reitman for more, including a look at the secretive Freewinds cruiseliner, a floating base where high-level Scientologists achieve "Operating Thetan" status, giving them the power to control matter, energy and time.
• Meanwhile, those keen to know Hubbard's work thoroughly should also see Battlefield Earth (Galaxy Press, Dh34), the story of an alien invasion of Earth in the year 3000.