Accused: Robert Xie arrives at the NSW Supreme Court on Wednesday. Photo: Daniel Munoz

Five members of the Lin family were fast asleep in their beds when someone lurking outside cut the electricity to their North Epping home on a cold, winter's night.

That person then let themselves in to the two-storey house and crept up the stairs, holding a hammer-like object and a rope. 

The NSW Supreme Court has heard the man allegedly clenching the object was a relative of the Lin family – Robert Xie.

In a retrial that began on Wednesday, Mr Xie, 52, appeared before a jury charged with murdering five people including his brother-in-law Min "Norman" Lin, 45, Mr Lin's wife Yun Li "Lily" Lin, 43, her sister Yun Bin "Irene", 39, and the Lins' two young boys Henry, 12, and Terry, 9 in July 2009.

He has pleaded not guilty to all charges.

In her opening address, Crown prosecutor Tanya Smith said Xie was motivated to kill his brother-in-law and his family out of jealousy and because he was infuriated with his perceived "subordinate status" within the family. 

"These perceptions invoked intense emotions on his behalf including anger and resentment and that the accused directed these emotions at Min and his wife [Lily]," Ms Smith said. 

"...also he was hurting the people that had not given him the respect and admiration he believed he was entitled to," she said. ​

The Crown alleged Xie was also motivated by a sexual desire he had towards a young female. 

Ms Smith alleged Mr Xie acted alone and highlighted that he knew the layout of the house well enough to manoeuvre around in the dark.

There was no forced entry to the Boundary Road house, which indicated the killer must have used a key to get inside.

"This was a well-planned crime of a personal nature with a single person who has carefully improvised a murder weapon," she said.

Nothing was taken from the house, ruling out the possibility of a robbery gone wrong.

Ms Smith alleged that Mr Xie disposed of the weapon he used to kill his wife's family but had failed to properly clean the floor of his garage.

It was here police found a blood smear that the Crown alleges consisted of mixed blood from at least four of the victims

"This one small stain was inadvertently left on the garage floor by the accused," Ms Smith said.

Bloodied footprints found in the upstairs bedrooms of the Lin family home were found to be consistent with ASICS sport shoes - a brand of shoe allegedly worn by Mr Xie. 

The Crown alleges that sometime between 2am and 5.30am, Xie walked into the first bedroom upstairs and used a hammer-like object and rope to kill Min and Lily.

After leaving them in a pool of blood in their beds, he went on to kill Irene in the second bedroom.

Finally the young boys, Henry and Terry, were killed in their bedrooms.

There was evidence to suggest the boys were awake and tried to run away from their killer before they were murdered.

"It's apparent from the blood splatter patterns – there was a furious struggle in that bedroom."

The trial continues before Justice Elizabeth Fullerton.