love this one

Time Crash may be only 15 minutes long but in that 15 minutes it establishes itself as one of the show's very best TV stories (even if it can't be called an episode as such).

Peter Davison and David Tennant bounce off each other brilliantly, with the banter between them consistently being snappy and funny to watch. It's always interesting to see how different incarnations of the Doctor interact with each other and 10's fanboyish enthusiasm for the 5th Doctor is refreshing among the multi-Doctor tendency to not have the incarnations get along.

Time Crash does everything right that Dimensions In Time got wrong. It offers a strong, simplistic narrative and plenty of screen time for the incarnations of the Doctor involved.

An excellent Children in Need sketch featuring the Tenth and Fifth Doctor. The plot is simple but fun, but really that's not relevant. The Chemistry between David Tennant and Peter Davison is superb and really what this piece is about. A standout sketch well worth watching.

A cute but insubstantial slice of nostalgia-who - not that it’s lack of meatiness matters. This sketch is unashamedly and justifiably aimed squarely at the fans. Within its short run time it doesn’t have to go anywhere or do anything. It’s a wry few minutes comparing, for the first time, the worlds of classic and modern Doctor Who. Seeing Peter Davison’s 5th Doctor back alongside Tennant’s incumbent 10th is a mind bending sugary treat. Once you have that you don’t need much more than some little gags.