Anthony Ler Wee Teang was born around 1967 in Singapore as the youngest of four children. His early life was marked by a troubled family background. His parents divorced when he was still young, and he remained emotionally distant from his siblings. He completed his primary and secondary education at River Valley English School and Thomson Secondary School. He enrolled in a polytechnic but dropped out during his first year after his father stopped funding his education. Known to be average academically, he later completed National Service and spent five years in the army.

After his military stint, Ler tried his hand at entrepreneurship, launching several businesses. However, all of them eventually failed, leaving him in serious debt. At the time of his arrest, he was working as a freelance graphic designer. Ler met Annie Leong Wai Mun when he was 19 and she was 15, through their church. They dated for five years before marrying in 1995. Their daughter was born on April 13, 1997.

The marriage deteriorated due to Ler’s repeated infidelities and financial irresponsibility. He had multiple affairs, one of which involved the mistress living in the same flat with Ler and his family. Leong eventually separated from Ler in 1999 and began divorce proceedings in early 2001. She also sought custody of their daughter.

In early 2001, while undergoing divorce proceedings, Anthony Ler devised a plan to kill his wife, Annie Leong, in order to gain full custody of their daughter and secure sole ownership of their jointly-owned flat, which was about to be sold. 

He also hoped to use the proceeds to settle his large debts. Between February and May 2001, Ler befriended a group of teenagers outside a McDonald’s in Pasir Ris. He began testing their willingness to kill, dangling a reward of S$100,000.

Most of the boys dismissed him as joking. However, one 15-year-old boy, known only as “Z” due to his minor status, eventually accepted Ler's request after persistent pressure. Ler manipulated Z, a simple-minded teen with an IQ of 93, using threats, fake mentorship, and gifts like a samurai sword. After two failed murder attempts on May 10 and 11, 2001—where Z backed out after seeing Annie with her young daughter—Ler increased the pressure and made death threats against Z and his family.

On the night of May 14, 2001, Ler lured Annie to the playground under the pretense of signing mortgage documents. While she went upstairs to retrieve a pen, Z ambushed her on the fourth floor, covering her mouth with a cloth and stabbing her in the neck, chest, and back. Annie staggered to her mother’s flat before collapsing. She later died at Tan Tock Seng Hospital from acute hemorrhage caused by stab wounds to the heart and lung.

Ler played the grieving husband in front of family and media, but his behavior during police questioning raised suspicions. 

Police found evidence tying him to the murder: the murder weapon was wrapped in a newspaper with a torn front page, which matched a paper found in his home. More damning was a confession from Z, who had told friends about the murder and ultimately confessed everything to police.

Ler was arrested and charged with abetment of murder on May 18, 2001. Z was also arrested and charged with murder but could not face the death penalty due to his age. At trial, prosecutors presented overwhelming evidence against Ler, including Z’s detailed confession, corroborating witness testimony from the teenage group, and recovered emails showing Ler communicating with Z about payment after the killing.

On December 5, 2001, the High Court found Ler guilty and sentenced him to death. 

Z was found guilty of murder but was detained indefinitely under the President’s Pleasure due to being a minor. Ler’s appeal was denied on March 4, 2002. He was hanged at Changi Prison on December 13, 2002. In his final days, Ler reportedly offered to donate his kidneys to his lawyer, Subhas Anandan, as a gesture of gratitude—a request that was respectfully declined.

Z remained in prison for 17 years. During incarceration, he studied diligently, earned his O- and A-levels, and later a university degree. He was described as deeply remorseful, and in 2018, President Halimah Yacob granted him clemency. Z was released on November 2, 2018, under conditions including electronic monitoring and curfew, and he continues to live anonymously under a permanent gag order.