A BACHELOR'S night of passion with a new girlfriend ended in terror when a man burst into the bedroom and said: 'That's my wife,' a District Court judge heard yesterday. Advertising designer Hui Tin-chee, 29, was in bed with the woman, Lam Yick-yu, 21, when the disturbance occurred, the court was told. Mr Hui said: 'We had sex. Then three men came in and asked me what I was doing there. One of them said he was Ms Lam's husband and that I was seducing his wife.' The court heard he was then punched, kicked and struck with a folding stool before being robbed and blackmailed by the men, who demanded $200,000. In the dock are Diep Wai-lun, 23, his brother Diep Wai-hung, 26, and Lee Yuet-wai, 23, all decorators. They all pleaded not guilty to robbing and blackmailing Mr Hui on September 16 last year. Prosecutor Jackson Poon said Mr Hui, a single man, met the woman in a karaoke bar the previous month. She told him she did not have a boyfriend and they began to see each other frequently. On September 15 last year the couple returned to her home in Tai Kok Tsui, Kowloon. 'Later they had sex,' Mr Poon said. 'At 12.15 am they were naked in bed. Suddenly someone opened the door and three males came in. Diep Wai-lun asked Mr Hui what he was doing there. 'He stated that he was Ms Lam's husband. As Mr Hui had had an affair with his wife, Diep Wai-lun demanded that Mr Hui pay $200,000.' The frightened lover was taken to the living room and assaulted by Diep Wai-hung and Lee, it was alleged. Mr Hui's bank cards were taken from his bag and he was forced to write down the PIN numbers, the court heard. The elder brother used the cards to withdraw $4,000, Mr Poon said. Mr Hui had been made to write down his telephone number and write an IOU for $200,000. The court heard Mr Hui was told he should page Ms Lam when he had the money. Mr Poon said the woman admitted to Mr Hui that Diep Wai-lun had been her live-in lover. But she claimed they were now separated. When the men left the victim found that $600 was missing from his wallet, counsel said. After the incident, Mr Hui and Ms Lam went to the police. At first he did not tell the complete truth because he feared Ms Lam was in league with the gang, the court heard. Later he went to Tseung Kwan O police station and told the full story. The police set up a trap for the three men using Mr Hui as bait, the judge was told. Mr Hui paged Ms Lam, as instructed, and a meeting was arranged at the Arc de Triomphe Restaurant, Mongkok, on September 25, last year. Mr Hui sat at a table with Ms Lam and the police moved in when he gave a pre-arranged signal by removing his spectacles. The defendants were all arrested near the restaurant. The court heard Diep Wai-lun put up a struggle and lashed out at a police officer with his mobile telephone. Ms Lam was arrested along with a fourth man who had arrived at the restaurant to collect the money. Both were later released. Mr Hui picked out all three defendants at an identification parade, Mr Poon said. The trial before Deputy Judge Yung continues.