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@yorrike This is where we have to be careful about numbering: Disney have started counting from the Christmas special, so I assume when you say episode 2 you mean 'Space Babies'? Whereas here in the UK, 'Space Babies' is episode 1.
Either way, I'd recommend carrying on at least until UK episode 3, 'Boom', which is written by Steven Moffat, and is excellent. The following one, '73 Yards' is, if anything, even better. In my humble opinion, of course.