HOUSTON, Texas (KTRK) -- A Houston used car lot owner is hoping dramatic surveillance video can help authorities catch the man who stabbed him in the head.Al Chi, owner of Wiz Used Cars, was working inside his modest office on Feb. 23 when a man came in, looking for a car."He was acting just like any regular customer. I get a lot of people coming in here looking at cars," recalled Chi, who has several surveillance cameras and a large fence installed on his property."He said he was interested in the 2015 Chevy Malibu that I had parked by the gate," he said.The two men can be seen on video looking at the car, shortly after that, the man asked Chi for a business card, and Chi said he had to go back inside to get it. What he didn't know was that the attacker followed him back into the office."I'm walking back inside, I did not know he was following me inside," said Chi, who demonstrated what happened next."I was getting him the business card," he said, reaching for a stack of cards on the desk. "When I turn around he's standing right behind me with a knife and he goes: 'Give me all the money you have in here otherwise I'll kill you.'"In the dramatic video, you can see the man hold a large knife on his right hand and take aim at Chi's head."I've never been attacked by a knife before, I'm panicking. I tell him, 'I don't have any money, I don't have any money.' Instinctively, I reach and give him my wallet and say here take it."The wallet wasn't good enough.The video shows the man looks at the wallet, then stabs Chi again. This time, the car lot owner makes a run for it. He ducks out of his office, and runs out the front door. Video shows he stumbles out of his parking lot and slides the gate shut.The attacker was almost as quick. He runs out, slides the gate back open, then jumps into his black Jeep and drives away.Chi went to the hospital and ended up getting four stitches, but he feels lucky."Thank God he didn't have a gun, because if he had a gun I think he would have killed me," Chi said.If you recognize the man in the video, you are urged to call the Harris County Sheriff's Office.