The Doctor's two companions, Amelia Pond and her new husband, Rory, are in the honeymoon suite of a space liner when it gets caught in the atmosphere of an Earth-like planet. It looks as if they are going to crash because of the force field the human colony has around it. The Doctor (Matt Smith) appears planet-side in hopes of saving his friends but the man in control is an old miserly guy who doesn't care if anyone dies. He actually owns most of the planet and is in charge of a huge cryogenic facility which houses "surplus population". If any family owes him money he freezes one of them as collateral. The Doctor (Matt Smith) tries to change his crotchety ways by going back in time and befriending him as a child. But this fails to change his present situation. Although he changes some events he also creates some that make the old guy how he is. Of course, being a Doctor Who episode there's some really strange stuff, such as the planet's fish which don't swim in water but swim in the atmosphere. There's a harrowing sequence in which a hungry shark breaks into the the boy's bedroom and nearly gets him and the Doctor.
I loved this Holiday Special. It's one of the more interesting versions of the Charles Dickens novel.