For several weeks now, my Tupperware glasses have been disappearing. I have interrogated the usual suspects, who claim they are not and never have been in possession of the missing items.
Today I took my trusty torch, and spied over the side of the primary suspect's bed. Bingo. The 5 missing items were located, along with a real glass and 7 partially used water bottles.
The suspect (Ernest) was later apprehended and was appropriately embarassed.
Just call me Nancy Drew.