When a stream of shampoo is fed onto a pool in ones hand a jet can leap sideways or rebound from the liquid surface in an intriguing phenomenon known as the Kaye effect. In earlier studies it has been debated whether non-Newtonian effects are the underlying cause of this phenomenon, making the jet glide on top of a shear-thinning liquid layer, or whether an entrained air layer is responsible. Herein we show unambiguously that the jet slides on a lubricating air layer. We identify this layer by

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... ooking through the pool liquid and observing its rupture into fine bubbles. The resulting micro-bubble sizes suggest this air layer is of sub-micron thickness. This thickness estimate is also supported by the tangential deceleration of the jet during the rebounding.