Podkayne of Mars is a science-fiction novel by American writer Robert A. Heinlein, originally serialised in Worlds of If (November 1962, January, March 1963), and published in hardcover in 1963. The novel features a teenage girl named Podkayne "Poddy" Fries and her younger brother, Clark, who leave their home on Mars to take a trip on a spaceliner to visit Earth, accompanied by their great-uncle. Plot summary The book is a first-person narrative consisting of the diary of Podkayne Fries, a 15-year-old (Earth years) girl living on Mars with her parents and 11-year-old brother Clark. Due to the unscheduled "uncorking" (birth) of their three test-tube babies, Podkayne's parents cancel a much-anticipated trip to Earth. Disappointed, Podkayne confesses her misery to her uncle, Senator Tom Fries, an elder statesman of the Mars government. Tom arranges for Clark and Podkayne, escorted by himself, to get upgraded passage on a luxury liner to Earth. During boarding, Clark is asked by a customs official "Anything to declare?" and facetiously answers "Two kilos of happy dust!" As he anticipated, his seemingly flippant remark gets him taken away and searched. This ploy serves to divert attention away from Podkayne's luggage, where he has hidden a package he was paid to smuggle aboard. Podkayne suspects the reason behind her brother's behavior, but cannot prove it. Clark was told it was a present for the captain, but is far too cynical to be taken in. He later carefully opens the package and finds a nuclear bomb, which he disarms and keeps. Much of the description of the voyage is based on Heinlein's own experiences as a naval officer and world traveler. Clark's ploy is taken from a real-life incident, related in Heinlein's Tramp Royale, in which his wife answers the same question with "heroin" substituted for the fictitious, but equally illegal, happy dust. Once aboard, they are befriended by "Girdie", an attractive, capable, experienced woman left impoverished by her late husband. Much to Podkayne's surprise, the normally very self-centered Clark contracts a severe case of puppy love. Podkayne overhears fellow passengers calling the Frieses "criminals" (Mars had been a convict colony) and "savages" (the Frieses have Māori ancestry). The liner makes a stop at Venus, which is depicted as a latter-day Las Vegas gone ultra-capitalistic. The planet is controlled by a single corporation; the dream of most of the frantically enterprising residents is to earn enough to buy