Knockout drops: colorless, tasteless and extremely dangerous. They’ve been around for decades and are used to incapacitate people in order to rob, rape and even kill them. "Spiking" is adding a sedative substance to people's food and drink without their knowledge or consent. The victim is rendered completely helpless and often suffers memory blackout - and crimes go unreported. "I didn't know why, but I knew something bad had happened," says Kate, recalling the night she was "knocked out". The following day, she realized she had been raped. Lawyer Jochen Link from the German organization Weißer Ring, which supports victims of crime, warns that the extent of the problem is being underestimated. Time and again, victims report blackouts even though they have consumed very little alcohol. The range of substances used is wide - from party drugs to sedatives and sleeping pills. Many victims feel ashamed or afraid that they won't be taken seriously.