It was a blue liquid in a crystal cut glass.
Something close to that anyway.
There were stairs leading down to what looked like a laboratory, of the old type.
Various colored vapors were swirling, so we refrained from looking over the bannisters.
We drank slowly, convinced, well almost, that we could tell if anything strange happened to us before it went too far.
The next day we woke up in a garden, lying on a red and green striped beach towel. The sun was already high and hot.
The adventure had begun before we noticed, while we were subdued by that blue drink we never asked for.