The police questioned Ng's family and friends, who all publicized her case to seek information of her whereabouts, which remained a mystery for more than a month.

[1] On 25 May 2011, a day before she supposedly disappeared, Celine Ng Swee Peng, a property agent, was celebrating her 36th birthday together with her friends at a bar in Fullerton Hotel.

Ang, who worked as a derivatives dealer at United Overseas Bank, told the duty officer, Corporal (Cpl) Muhammad Nazri Parjali, that she found Ng not present in her condominium when she woke up at 10am on the day she went missing.

[5][6] After investigating for more than a month, the police were still unable to locate any clues on Ng's whereabouts, and their efforts drew a blank after nationwide searches in places like hospitals, prisons or institutions.

The Immigration and Checkpoints Authority (ICA) also confirmed that Ng did not leave the country based on their records of people going in and out of Singapore.

[7] The police therefore suspected that something untoward might have happened to Ng, and assuming that Ng was possibly dead, the police conducted a nationwide search around the forested areas of Singapore, including forested areas nearby the National University of Singapore (NUS), West Coast Park and Kent Ridge Park, for possible human remains as part of their investigations.

[2] After a search around Singapore from 29 June to 5 July 2011, the police turned their attention to Clementi Woods Park, where a team of officers discovered a complete set of a human skeleton hidden in the undergrowth, and despite a post-mortem examination by Dr George Paul, a forensic pathologist, he was unable to determine the cause of death and he speculated that the death of Ng might have occurred at least 41 days before, and the police also conducted forensic tests to identify the skeleton.

In 2009, both Ng and Ang, and a third friend established a cafe, although it was sold off in the end due to their respective commitments to other lines of work.

To make it appear that Ng had gone on an overseas trip, Ang took her friend's passport, packed an overnight bag and threw it down a rubbish chute.

After this, Ang drove off in Ng's car, and she drove all around Singapore, including the West Coast area, the East Coast area and Changi, to search for a safe place to hide the body, but she aborted the search after arriving at Changi due to daybreak, out of fear that she might be seen.

[36] On 16 July 2015, four years after her arrest for the murder of Celine Ng, 40-year-old Ang Soo Hoon was finally put on trial for killing her flatmate.

A spokesperson of the Attorney-General's Chambers (AGC) told the media that the murder charge was reduced after carefully considering the facts of the case, although no exact reasons were given behind this decision.

Ang, who pleaded guilty to the manslaughter charge, also faced lesser charges of providing false information to the police and dishonest misappropriation of property, which Ang also admitted to in her plea of guilt submitted before the trial judge Tay Yong Kwang of the High Court.

[32][37] The prosecution, led by Deputy Public Prosecutor (DPP) David Khoo, pressed for a jail term of not less than 13 years.

DPP Khoo highlighted to the court that the circumstances of the killing were based solely on Ang's account, and the cause of death could not be objectively ascertained due to lack of supporting evidence.

[34][32] On the other hand, the defence, led by the late Subhas Anandan's nephew Sunil Sudheesan, sought a sentence of around ten years' jail.

[46] In December 2011, the murder case, which shocked the nation, was listed as one of the most significant topics reported in the media nationwide.

[47] By end-2015, the case of Ang Soo Hoon was reported as one of the top ten topics to make headlines nationwide in July 2015.

[48] Additionally, in January 2014, it was reported that due to the Celine Ng case, there were increased measures for security in condominiums to prevent crime from happening and maintain the safety of the residents.

In the chapter titled Missing, which covered the Celine Ng case, Ang was described by the author as someone who was not a "hardened criminal" and never committed any minor offences prior to the case, and yet something inside Ang snapped and it caused her to kill her best friend and ex-girlfriend over an offensive remark, classifying Ng's death as a "crime of passion committed in a moment of madness".