My dad used to work as a lighting technician in the main theater of the Cultural Center of the Philippines (CCP) during the latter part of the Marcos regime. The CCP serves as a venue to showcase Filipino culture and art, and houses exhibit halls, a library and several theaters.
The CCP has seen it share of popular local and international personalities. That day, during dad's shift, their crew were informed that the president's first lady, Imelda Marcos, will be watching the play. The Presidential Security Group (PSG) thoroughly swept the place for anything and anyone suspicious.
After that, my dad and the sound technician (let's call him Roy), went up to the control room behind the stage (it's elevated, think two story backstage) and started checking their equipment to get ready for the play. Their area allows them to see the stage without being seen by the audience. Imagine the recording studios with the glass panel - that's pretty much how it looks like. On the first level across them (still behind the stage) are two PSG men, stationed in that area.
The play started without a hitch but during the intermission, the two PSG guys came running inside the control room. My dad and Roy got a little worried - during that time, getting in trouble with the Marcoses either mean torture or death.
One of PSG guys spoke up and asked whether someone went through the room. My dad and Roy told them they haven't seen anyone go through the door. Unconvinced, the PSG guys pointed to a door on the right. Roy said that door has been locked for a long time but gave them the key anyway so they could check it themselves. They did and found the tiny room dusty and empty (no trap doors or anything).
For a couple of tough guys, they started looking a little shook up. They told my dad and Roy that just a few minutes ago, before the intermission, they saw a lady with long hair and white clothes entering the room--running, then disappearing. My dad and Roy looked at each other, shrugged and told the PSG guys that it happens a lot there (the whole CCP in fact). (Courtesy: yourghoststories)