Elleke Boerhaave's husband is one of the wealthiest and most dangerous men in the whole solar system. She has successfully separated from him, but, to pre-empt the custody battle over their eleven-year-old daughter Patt, he has kidnapped their child and whisked her off to a land with which no Earthly nation has an extradition treaty: Mars. Mrs Boerhaave hires Hi, a man with a very special set of skills, to perform an extraction: to fly to Mars, locate Patt, and bring her back to Earth.
Even for Hi, this is a highly perilous mission against near insurmountable odds. Flights to Mars take 6-9 months, and every steerage berth is logged, so Boerhaave will know he is coming. Boerhaave's compound, on the remote flanks of the mountain Arsis Mons, is guarded by a squad of heavily armed, highly trained soldiers, as well as every anti-intruder device money can buy. And as if that weren't enough, if Hi does manage to get to Patt, there's no obvious way to bring her back to Earth.
Which is just the kind of challenge Hi likes.