Lewis Dale admits to stabbing grandmother to death after taking M-Cat A grandfather has told a jury of his wife's last words to their grandson before he attacked her while high on M-Cat - formerly a 'legal high'. Allan Dale, 80, told a jury grandson Lewis had knifed him before he turned on his 78-year-old grandmother, Irene Dale, as they lay in bed. Mr Dale told Hull Crown Court: 'I heard Irene say: "What are you doing Lewis?" He went around to my wife and he stabbed her. He told a court he had given his grandson somewhere to live for 10 days because he was in trouble with the police. Lewis Dale, 17, dressed in black suit and black tie wept as his grandfather gave evidence from behind a screen in the court. The teenager has admitted the stabbing saying at the time he had been taking M-Cat a former legal high. Mr Allan Dale told Hull Crown Court: 'It was just like Norman Bates in Psycho. That is a true description. He just came into the bedroom with his hood up on his dressing gown. The next thing was Lewis stood over me. He lunged at me plunging the knife in my chest. I got up. He must have thought I was going for him and he stabbed me in the side. He hit me with a kitchen knife on of the hardest in the block. I heard Irene say: "What are you doing Lewis?" She had the duvet in front of her to protect herself. She was stabbed twice. I could not do anything. I was covered in blood. He threw the knife at me and it ended up sticking in the floor. After he threw the knife he went straight down stairs. 'I tried to lift my wife's chin off the bedroom cabinet. And put her in the recovery position, but was not strong enough. I didn't realise how badly injured she was. I shut the bedroom door and tried to move the cabinet to block it I did not know she had been stabbed twice. I heard Lewis downstairs shout three times: "Give me some money! Give me some money and I will go! The next thing I heard he had shut the front door and gone. He had locked me in. I was in the front bedroom window and looked out and saw the taxi driver. Lewis waved to me as if I was going on holiday. When he waved, I thought he was going to come back. I thought he thought maybe both of us were dead. He obviously thought he had locked us in. I called 999. The police and paramedics came in. I sat downstairs and took my shirt off, because it was covered in blood. 'Then I said: "He's took my television." He also took a jar of 50p pieces. That was my taxi money.  Dale, of Brough, East Yorkshire, is on trial at Hull Crown Court denying charges of murdering Irene Dale, 78, and attempting to murder her husband Allan Dale, 80, at their home in Hull, around 2am on April 27 2013. Dale's defence team say he was suffering from drug induced psychosis which is a partial defence to a charge of murder. Under cross-examination from defence barrister Andrew Robertson Allan Dale admitted he told the police. I can only describe Lewis as psychotic at the time, due to the way he lunged at me and went around the bed to stab Irene. I could not make sense of what was happening. He said: 'What happened was completely and utterly out of the blue. He came into the bedroom and stabbed us. He didn't say a word.' Under re-examination from Adrian Strong Allan Dale admitted he had no training in mental health and no knowledge of his grandson having mental problems.