Question: What is the book that was based on the crimes Colin Howell is convicted of ?

Context paragraphs:
Colin Wallace: John Colin Wallace is a former British member of the Intelligence Corps in Northern Ireland and a psychological warfare specialist.  He was one of the members of the intelligence agency-led 'Clockwork Orange' project, alleged to have been an attempt to smear various individuals including a number of senior British politicians in the early 1970s.  He also attempted to draw public attention to the Kincora Boys' Home sexual abuse scandal several years before the Royal Ulster Constabulary finally intervened.  He was wrongly convicted of manslaughter in 1981, for which he spent six years in gaol, until 1987.  The conviction was later quashed in the light of new forensic and other evidence that raised serious questions about the dubious nature of the evidence used to convict Wallace initially.  The journalist Paul Foot, in his book "Who framed Colin Wallace?" , suggested that Wallace may have been framed for the killing, possibly to discredit the allegations he was making.  This view was similarly expressed by Alex Carlile QC (now Lord Carlile), who later speculated that this may have been the motive not just for the alleged frameup, but also for murder.

Sarah Howell: Sarah Howell is a noted cartoonist and educator based in Brunswick, Melbourne.  Howell is often involved in projects that promote the Australian comic book art scene.  She is a founding member of Squishface Studio, a workspace for artists in which customers looking to buy comics can walk in and watch artists work.  She self-publishes zines and mini-comics.  Howell is also the director of the Homecooked Comics Festival.  She works as a cartooning tutor at Boxhill Community Arts Centre and a graphics novelists at the Centre for Adult Education in Melbourne.

The Secret (TV series): The Secret is a 2016 Northern Irish ITV mini-series based on "Let This Be Our Secret", Belfast journalist Deric Henderson's account of the double murder of Lesley Howell and Constable Trevor Buchanan, whose bodies were discovered in a fume-filled car in the garage of a property in Castlerock, County Londonderry, in Northern Ireland in May 1991.

David Bergman (journalist): David Bergman (born 1965) is a British human rights activist and investigative journalist based in Bangladesh, who worked at the "New Age", a Bangladesh national newspaper.  He is known for his reportage on war crimes committed during the Bangladesh Liberation War.  An investigative documentary on the subject he worked as a reporter and researcher for British television in 1995 won an award.  He was convicted of contempt by Bangladesh's special war crimes tribunal in 2015 for contradicting the official figures of the war.

Colin Howell: Colin Howell (born 14 March 1959) is a Northern Irish convicted double murderer.  The murders and surrounding story were the subject of an ITV drama series "The Secret" broadcast in April and May 2016.

Laura Caldwell: Laura Caldwell is a former civil trial lawyer who is now a law professor at Loyola University Chicago School of Law, director of Life After Innocence, published author of 14 novels and one non-fiction book (to date).  Her latest book is "Anatomy of Innocence: Testimonies of the Wrongfully Convicted" (Liveright, 2017), which tells the incredible true stories of over a dozen innocent men and women who were convicted of serious crimes and cast into the maw of a vast and deeply flawed American criminal justice system before eventually, miraculously being exonerated.

Colin Pitchfork: Colin Pitchfork (born 23 March 1961) is a British convicted murderer and rapist.  He is the first person convicted of a crime based on DNA fingerprinting evidence, and the first to be caught as a result of mass DNA screening.  Pitchfork raped and murdered two girls in Leicestershire, the first in Narborough, in November 1983, and the second in Enderby, in July 1986.  He was arrested on 19 September 1987 and sentenced to life imprisonment on 22 January 1988, after admitting both murders.

Randy Roth: Randy Roth is a convicted murderer and thief from Washington.  He was convicted of the 1991 murder of his fourth wife, Cynthia Baumgartner Roth.  He was suspected but never tried for murdering his second wife, Janis Roth, in 1981.  In both deaths he was the only witness, he claimed the activity that led to the death was the idea of his deceased wife, and the bodies were cremated as quickly as could be arranged.  He was also convicted of stealing in the form of defrauding insurers and the Social Security Administration and was sentenced to one year for theft and 50 years for first degree murder in 1992.  At least two true crime books are based on Roth's crimes, "A Rose for Her Grave" by Ann Rule and "Fatal Charm" by Carlton Smith.

Let This Be Our Secret: Let This Be Our Secret is a true-crime book by award-winning British journalist Deric Henderson about how Colin Howell, aided and abetted by his mistress and fellow-Christian Hazel Stewart, callously killed their spouses and buried the truth for 18 years by making the deaths look like a suicide pact.

Elizabeth Smart kidnapping: Elizabeth Smart was abducted at the age of fourteen from her bedroom in Salt Lake City, Utah on June 5, 2002.  She was rescued by police officers nine months later on March 12, 2003, in Sandy, Utah, about 18 miles from her home, in the captivity of Brian David Mitchell and Wanda Ileen Barzee, who were indicted for her kidnapping, but initially ruled unfit to stand trial.  After both defendants were found competent to stand trial, Barzee was convicted in 2009 and Mitchell was convicted in 2010.  Mitchell was held in the Salt Lake County Jail following his sentencing on May 25, 2011.  On August 31, he was transferred to a federal prison in Arizona to begin serving a life sentence for his crimes.  The abduction of Elizabeth and her rescue were widely reported and were the subject of a made-for-television movie and a published book.

Supporting paragraphs: Colin Howell The Secret (TV series)
Answer: Let This Be Our Secret