After a brief airing of the first episode six months earlier, K-9 finally makes its series debut in the UK with the third episode, "The Korven". And strictly speaking, this aired two hours earlier than "The Eleventh Hour" did (were they capitalizing on Doctor Who's publicity? Perish the thought!), but as they're airing two episodes a week at this point, it's easier to lump them together than try to do it strictly chronologically. I'm sure you care deeply about this.
All right, that's not fair; both episodes do actually do a decent job of making Gryffen and K-9 seem like they should definitely be worried about their chances. The problem is more that it's still hard at this point to really care about the other characters: the teenagers have already been reduced to basic characteristics (Darius likes Jorjie and dislikes Starkey, Starkey's the rebel with a heart of gold, etc.), acting more as ciphers than real people. Far and away the best character is Professor Gryffen; this might be because Robert Moloney is a more experienced actor than the others, but it's also because they've actually given him characteristics to distinguish himself as an actual person (his agoraphobia, but also his calm behavior in the presence of Ahab the bounty hunter, offering him tea and casually chatting with him). There's also an effort to introduce a recurring villain in the form of the Department Head of Security, Inspector Drake, but he's portrayed as such a slimy git that while it's easy to loathe him, it doesn't do much for their efforts to flesh this show out. (Although placing a fake bomb as a publicity stunt? That is pretty slimy...)
Ultimately the problem with both of these episodes is that they're too straightforward; we don't get much in the way of nooks and crannies in the plot to explore, and subtlety isn't K-9's strong point. Even something like making K-9 initially appear to have been a killer pre-amnesia in "The Bounty Hunter" falls flat, because we know that something will happen to vindicate K-9, and we're right. These two episodes aren't actually bad, but they are rather unsophisticated. This is a format that seems like they could actually do something with, but thus far they've been content to play it safe -- but playing it safe isn't really going to cut it for the whole series.