The episode takes place entirely in the TARDIS, the doctor's living transport unit which is permanently cloaked to look like a police box. The TARDIS is much larger on the inside than it is on the outside, and that is where the fun in this episode comes in. This episode is very much fan-service, as it allows you to explore the TARDIS control area and the Doctor's reading room, which has been seen before on screen and contains artifacts the Doctor has picked up on his travels. The storyline sees the TARDIS stuck in a time vortex, with the Doctor and Amy having to find a way out. The duo's task becomes much harder once the episode's villain is revealed. I enjoyed the villain of this episode, since it was motivated by something other than hatred for the human race.
The voice actors seem to be showing more emotion in their performances. There were a few flat lines, but they occurred much less than in previous episodes. The times when the Doctor and Amy were in danger were conveyed with the proper mix of excitement and fear, as they would be in the television series, which really helped to keep you engrossed in the storyline. The music and sound effects are once again great, as they sound like they would in an episode from the series. The aural portion of these episodes were always top-notch, with the exception of the vocal performances, but now the voices are nearing the same level.
The puzzles in this episode are, for the most part, fun and original. The puzzles have been improved a lot since the previous episodes. I particularly enjoyed a puzzle where the collectible facts are used as part of the puzzle. I enjoyed it when the collectibles were used as part of the game in the later episodes of Telltale's Strong Bad's Cool Game for Attractive People, and I'm glad to see Sumo Digital taking the same route here. The middle of the game was hampered, however, by the same snag that hurt the previous episodes. Puzzles are repeated, both from previous episodes, and within the same game. The puzzle that I found the weakest of the puzzles so far, the maze puzzle from the first episode, is once again used here. And, just like the first episode, the puzzle is repeated (though it's only used two times this episode, as opposed to three in the first). Another puzzle also returns from a previous episode, but it is used well within the context of the game, and only happens once. It's really a shame that puzzles were repeated here, as it was really unnecessary to do so.
TARDIS is a step in the right direction. The episode is fun, the puzzles are mostly enjoyable, the voice acting has improved a lot, and the music and sound effects are as good as ever. The repeated puzzles bring the overall enjoyment of the game down a bit, but this is still the best episode of Doctor Who: The Adventure games so far.
4 out of 5