Podkayne of Mars

Podkayne of Mars is a science fiction novel by Robert A. Heinlein, originally serialised in Worlds of If (November 1962, January, March 1963), and published in hardcover in 1963. The novel is about a teenage girl named Podkayne "Poddy" Fries and her younger, asocial genius brother, Clark, who leave their home on Mars to take a trip on a spaceliner to visit Earth, accompanied by their uncle.

This book, along with Starship Troopers, shows Heinlein moving away from his old, comfortable territory of juvenile science fiction novels. Both books were written for a publisher expecting to market a juvenile science fiction novel, and both raised serious objections from the publisher.

Plot summary
The book is a first-person narrative in the form of Podkayne's diaries. Podkayne is 15 in Earth years (a bit over eight Martian years) while her genius younger brother Clark is 11 earth years (6 martian years). Due to the unscheduled "uncorking" (birth) of 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, just in time 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, in typical Clark-fashion, 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.

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 a single share in it, which guarantees lifelong financial security. Just about anything goes, as long as one can pay for it. The penalty for murder is a fine paid to the corporation for the victim's estimated value plus his projected future earnings. On a less serious level, Heinlein anticipated, by over forty years, television ads in taxicabs (in the book, holographic), which have since been implemented in taxicabs in major cities worldwide.

The Fries are given VIP treatment by the Venus Corporation and Podkayne is escorted by Dexter Cunha, the Chairman's dashing son. She begins to realize that Tom is much more than just her pinochle-playing uncle. When Clark vanishes and even the corporation is unable to find him, Tom reveals that he is on a secret diplomatic mission, and the children have been his protective coloration -- instead of an accredited representative to a vital conference on Luna, Tom appears to be a doddering uncle escorting two young people on a tour of the solar system. Clark has been kidnapped by functionaries of a political faction opposed to Tom.

Podkayne makes an ill-judged attempt to rescue Clark by herself and falls into the kidnappers' clutches as well -- only to find her uncle caught too. The captors' scheme is to use the children to blackmail the uncle into doing their bidding at the Luna conference. Clark quickly realizes that once Uncle Tom is released, no matter what happens, their kidnappers will have little reason to keep their prisoners alive. He is prepared, however; he engineers an escape, leaving the nuclear bomb behind to blow up the kidnappers.

Two versions of the ending
In Heinlein's original ending,. This did not please his publisher, who demanded and got a rewrite over the author's bitter objections. In a letter to Lurton Blassingame, his literary agent, Heinlein complained

In the original ending,

In the revised version,

The 1995 Baen edition includes both endings, Jim Baen's own edited postlude to the story, and a collection of readers' essays giving their opinions about which ending is better.

Tropes:

 * Enfant Terrible: Clark
 * Expy: Podkayne herself is an expy of an earlier Heinlein character "Puddin'", the lead character in some romance short stories included in Expanded Universe.
 * Executive Veto: Because of the original ending.
 * Lost Aesop: The revised ending has Uncle Tom chastise Podkayne and Clark's parents for being hands-off parents - which wasn't set up very well (if at all) during the novel.
 * Mega Corp: The Venus Corporation
 * Population Control: Mentioned as being necessary on Mars, but doesn't affect the story at all.
 * Revised Ending: See above.
 * Science Marches On: Jungle Venus.
 * Shout-Out: Inverted. Podkayne appears in Heinlein's later novel The Number of the Beast, attending the party at the end along with many other Heinlein characters from previous books.
 * Society Marches On: Podkayne mentions that she wants to become the first ever female spaceship captain. Eileen Collins captained a spaceship in July 1999.
 * Write What You Know: As a Navy veteran, Heinlein was familiar with spending long times aboard ships.

Spoilers for the original ending: