In the video, Elisa Lam is behaving strangely in an elevator at a discount hotel in a sketchy Los Angeles neighbourhood.
The nearly two-and-a-half-minute security video, which police released earlier this week, shows the missing Vancouver student pushing buttons for multiple floors. When the doors don't close, she darts out and quickly looks from side to side. At one point, she stands outside the elevator and moves her arms around wildly. After pressing several buttons again, she eventually walks away.
Ms. Lam, 21, mysteriously vanished more than two weeks ago. Police have said her disappearance is "suspicious and may suggest foul play."
Ms. Lam, who was in touch daily with her family before she vanished, was last seen without her eyeglasses at the Cecil Hotel on Jan. 31. She never checked out.
The hotel, which rents rooms with shared bathrooms for just $65 (U.S.), is located near L.A.'s Skid Row neighbourhood, which is a hive for drug and other criminal activity. The hotel got an upgrade a few years ago under new ownership but previously housed low-income permanent residents.
Police have said they don't know why the University of British Columbia student was in southern California but that her final destination was Santa Cruz. She arrived in L.A. on Jan. 26.
Her family appeared at a police news conference last week.
Ms. Lam is described as being of Chinese descent, five-foot-four and weighing about 115 pounds. She speaks English and Cantonese.