The incident occurred just after 11 p.m. Saturday, and authorities are still searching for a suspect, according to the report.
Police told KSAT the woman was walking out of the theater when a man approached her from behind and stabbed her multiple times before escaping out a back door. EMS took the woman to University Hospital in critical condition, but as of Sunday morning, her condition was upgraded to stable.
Even though there were no eyewitnesses, investigators were able to obtain a description of the suspect, thanks to surveillance video. Police have not yet released a description of the man.
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