"Evil" manipulator Cecilia Steyn, teen killer Marcel Steyn and Zak Valentine - who even conspired to murder his wife - were served with multiple terms of life imprisonment on Monday for their four-year killing spree in Krugersdorp.

Cecilia Steyn was served with 13 life terms and Valentine received eight life terms.

Judge Ellem Francis served Marcel Steyn with 15 years' imprisonment for murders committed before she turned 18, and life for the murders committed after her 18th birthday.

Cecilia Steyn, a policeman's wife and mother of two, and insurance broker Zak Valentine, together with Marcel, were part of a group of six people who conspired to kill 11 people between 2012 and 2016 on the West Rand. They had pleaded not guilty but were convicted in June of murder as well as a string of other offences, including robbery and illegal weapons possession.

The other three admitted guilt and were sentenced separately. They are Marcel's brother Le Roux Steyn, jailed for 25 years; Marcel's mother Marinda Steyn, a former schoolteacher, who is serving 11 life terms for the killing spree; and printmaker John Barnard, who was jailed for 20 years.

"The Krugersdorp area was struck by a man-made tsunami and the driving force behind it  was accused two [Cecilia Steyn]," Francis said during sentencing on Monday.

The victims were stabbed or strangled.

The murders started after a feud within a church group that aimed to convert satanists to Christianity, with members of the group the early targets. This morphed into killings for financial gain. 

CECILIA STEYN

Francis described Cecilia as a " a highly intelligent and streetwise woman who was able to deceive many".

"She made life hell for those she did not get along with. She used and abused the generosity of others."

The court described her as the mastermind and the only person who benefited from the murders.

"Her deeds were motivated by personal gain," said Francis.

"She is a thoroughly evil person who is not capable of rehabilitation. I'm deeply concerned about the people she will be mingling with in prison."

Cecilia's character, he said, was such that she should be permanently removed from society.

ZAK VALENTINE

The judge said the victims' families had suffered "palpable" pain, which had been evident in their testimonies during the trial.

"None of the deaths was accidental. The victims were carefully identified, the murders were carefully executed.

"I don't understand why accused one [Zak Valentine] and three [Marcel Steyn], considering that they are intelligent, could believe the utter rubbish they were fed by accused 2 [Cecilia Steyn]," contended Francis.

"I simply do not understand why accused one [Zak] arranged for his own wife to be killed."

MARCEL STEYN

The judge said Marcel Steyn proclaimed to have showed remorse, but it was not remorse in the "true sense of the word".

"What counts against her is that her involvement did not amount to one murder."

During the trial, Marcel admitted to being on the scene when they were instructed by Cecilia to murder Mikeila Valentine because she was a "loose string", and she participated in the actual attack on the travel agent. She also accompanied her mother to kill pastor Reginald Bendixen. She testified that she was also there when businessman Peter Meyer called out Psalm 23 while he was being stabbed by Valentine.

The judge said Marcel Steyn was a good candidate for rehabilitation. "Life sentence does not rule out prospects of  rehabilitation. Although she has a high IQ, she lacks emotional intelligence. She was described as immature. She has no trace of being a psychopath."

THEIR VICTIMS AND THEIR ARRESTS

2012

• July 26: Natacha Burger, 33, and Joyce Boonzaaier, 68.
• August 14: Pastor Reginald Bendixen, 75.
• October 11: Mikeila Valentine.

2015

• November 27: Peter Meyer, 51, and his wife, Joan, 47.
• December 16: Jarod Mitchum Jackson, 44.

2016

• January 27: Glen McGregor, 57.
• May 10: Anthony Scholefield, 64.
• May 26: Kevin McAlpine, 29.
• May 31: Hanlé Lategan, 52.
• June: Marcel and Le Roux charged with murder.
• July: Zak, Cecilia and Marinda arrested.

2017

• December: John Barnard pleads guilty. He is sentenced to 30 years in jail, with 10 years suspended on condition he testify against the other accused. 

2018

• May 16: Marinda and Le Roux are jailed after admitting their guilt. Marinda is sentenced to 11 life sentences, Le Roux to an effective 25-year prison term.

2019

• June 3: Cecilia, Marcel and Zak are found guilty.
• August 12: Evidence in mitigation of sentence for the trio is expected to be heard in the Johannesburg high court.