The most chilling murders are the ones committed by the people you trust the most.

In March 2012, former EastEnders actress Gemma McCluskie vanished from the flat she shared with her older brother Tony in Shoreditch, east London. Friends, family and even celebrities rallied together in desperate searches. Tony was right there in the middle of it – hugging relatives, handing out flyers, texting Gemma’s phone as if she might still reply, telling everyone “we’ll find her.”

He already knew exactly where she was.

He had beaten her to death, hacked her body into six pieces, stuffed the remains into a suitcase and black bags, and dumped them in Regent’s Canal – all while high on the super-strength skunk cannabis he smoked from the moment he woke up.

Tony McCluskie’s cold-blooded cover-up lasted only nine days before police found Gemma’s headless torso floating in the water. Within hours the finger of suspicion pointed squarely at the brother who had been “grieving” so publicly.

What emerged at the Old Bailey was a story of jealousy, drugs and unimaginable betrayal that still shocks Britain more than 13 years later.

Gemma Rose Veronica McCluskie was born on 5 February 1983 and stood just 4ft 11in, but she lit up every room she walked into. She landed a role in CBBC’s No Sweat at 14 and in 2000 joined EastEnders as Kerry Skinner, the bubbly great-niece of legendary character Ethel Skinner. She appeared in over 40 episodes, dated Robbie Jackson on-screen and became friends with Michelle Ryan’s Zoe Slater. Although her time in Walford was short, fans never forgot the cheeky teenager with the huge smile.

After leaving the soap in 2001, Gemma worked as a barmaid in Shoreditch pubs and cared for her seriously ill mother Pauline, who was battling a brain tumour. She still lived with her mother and 35-year-old brother Tony in the family flat on Pelter Street. Tony, a window cleaner, was unemployed, permanently stoned and, according to Gemma, “puts a spliff in his mouth first thing in the morning and doesn’t know what he’s doing.”

Friends said Gemma had reached breaking point. She wanted him out.

On 1 March 2012 the final row exploded. Tony, high again, left the taps running and flooded the bathroom. Gemma came home, lost her temper and told him to pack his bags. Witnesses heard her screaming down the phone at him that afternoon.

That evening she was seen on CCTV buying a kebab near the flat around 8pm. She never made it out again.

Prosecutors said Tony grabbed her wrists, punched her to the ground and struck her head at least twice with a blunt instrument, causing catastrophic brain bleeding. He then spent hours dismembering her body in the bath using a knife and meat cleaver, cleaning the flat with bleach and chemicals.

The next day he sent his girlfriend a casual text: “Morning, sorry crashed out last night. Feeling a bit better today.”

Then he texted his dead sister’s phone: “Hi Gem, letting you know I’m at the hospital. Mum is doing really good… Love ya xx” – the first time he had ever signed off “Love ya” to her.

CCTV captured him dragging a heavy suitcase toward a minicab office, struggling with the weight, then heading toward Regent’s Canal. He dumped the case and black bags containing Gemma’s arms, legs and torso.

Over the following week Tony played the role of distraught brother perfectly. He reported her missing to police. He joined search parties. He comforted his brother Danny with hugs and tears, saying “please don’t let it be Gemma.” He handed out missing posters. He even received hoax ransom calls demanding £2 million – calls police later traced to a teenager in Kent who had no idea he was speaking to the actual killer.

On 6 March 2012 a suitcase snapped open in the canal and Gemma’s torso floated to the surface. She was identified by a distinctive tattoo on her back. Limbs were recovered in bin bags days later. Her head was not found until September 2012.

Tony was arrested on 10 March 2012 and charged with murder.

At trial in January 2013 he admitted manslaughter but denied murder, claiming he “lost control” and had no memory of the killing after Gemma allegedly came at him with a knife. The jury took less than three hours to reject his story and find him guilty by 11-1 majority.

Sentencing him to life with a minimum 20 years, Judge Fulford said Tony had acted in an “utterly cold-blooded and determined way” to cover his tracks and had tried to destroy his sister’s reputation even after death.

Gemma’s brother Danny later told documentaries: “He’s a monster for what he done to my little sister… He put his arms round me and said we’ll keep searching. I’ll never forget it. He’s a scumbag.”

Their father Anthony initially said he would not desert Tony, but the family has since cut all contact. Tony McCluskie, now 48, remains behind bars serving his life sentence and will not be eligible for parole until at least 2033, when he will be 56.

The case has been revisited in multiple documentaries, including Crimes That Shook Britain, Evidence of Evil and most recently Murder in the Family on Channel 5, with Gemma’s loved ones still speaking of the double heartbreak – losing both children in one act of evil.

A talented young woman with her whole life ahead of her was slaughtered by the one person who should have protected her – all because her drug-addicted brother couldn’t stand that she wanted him gone.

And for nine sickening days he looked her friends and family in the eye while knowing her dismembered remains were rotting in a London canal.

That is the true measure of Tony McCluskie’s depravity.