Plot: While traveling through the Time Vortex, the TARDIS picks up a distress signal, and materializes on a cargo ship on a collision course with a Sun. The Doctor and Martha only have 42 minutes to save the ship and her crew.
Spoilers: (highlight to view) Oh, and the TARDIS is trapped in a vent chamber which has been sealed off due to the intense heat, the main engines have been crippled, the controls for the auxiliary engines are in the front of the ship and there are 29 deadlock sealed doors between the crew and them, and there is an alien presence that can infect anyone, even the Doctor.
At least Martha is trying to make it through the deadlock seals to the auxiliary engine controls (by fighting trivia quizzes), and the Doctor is a genius.
Review: The premise behind "42" is a sound one.
There is a ship that will crash into the sun in 42 minutes.
You would think that this would be a fast paced episode with lots of drama, and lots of dread.
Well, if you thought that, you would be right.
This was a really good episode.
First, let's talk about the monster.
I like the "simple" monsters.
You know, the ones who don't have lots of complex prosthetic make up, faces that can't show emotions, and a good "signature" line.
For instance, my all-time favorite monster was "The Empty Child" from the 2005 series.
That was a true classic monster.
Well, this monster kind of reminds me of that.
Basically, take a human, throw on a sci-fi style welding mask, and have them say "Burn With Me".
While it wasn't as creepy as the gas mask people from "The Empty Child/The Doctor Dances", it was still a great monster.
Then there was the drama.
You have the automatic time limit of 42 minutes already in place, but then place Martha in an airlock being jettisoned into the Sun . . .
. . . adds a bit more drama to the situation.
Add to that the use of very powerful music, and the occasional silence, and you have a very powerful story.
And then there is the family element.
In the last episode, Mr. Saxon warned Martha's mom about how dangerous the Doctor is, and that storyline continues with Martha's phone being upgraded with "Universal Roaming", just like Rose's.
While many of the good stories would have made better serial episodes, take "Dalek" for example, this one would have been harmed by it.
I really couldn't think of anything wrong with this one, and because computers always give you grief at the worst times, I'm giving "42" 5 Deadlock Seals out of 5.