The greeting first appeared in 1967 on the "Star Trek" second-season opening episode, "Amok Time". Among other things, the gesture is known for being difficult for certain people to do properly without practice or the covert pre-positioning of the fingers. Actors on the original show reportedly had to position their fingers off-screen with the other hand before raising their hand into frame. This difficulty may stem from variations in individuals' manual dexterity. It is parodied in the 1996 motion picture "" when Zefram Cochrane, upon meeting a Vulcan for the first time in human history, is unable to return the gesture and instead shakes the Vulcan's hand.