There is a real “end of school term” vibe to this story. You feel like the team is letting their hair down and doing something a bit different. K9 is put to fantastic use, helping Clyde cheat on the school test, dobbing him in to Sarah-Jane, fighting with Mr Smith. He was made for this show. Part of me wished that the Slitheen-Blathereen had not turned out to be baddies, as I was enjoying the quirkiness of having good guys as the monsters of the week. However, their underhanded story arc serves the plot very nicely. There is a nod to Day of the Triffids with how the Rackweed spreads and starts to pick off humanity.