Luke Smith returns home from University, bringing with him a highly volatile biological culture which Mr Smith offers to incinerate (his washing). On his mum's instructions, Luke updates the Alien Files with what he knows about Mrs Wormwood, the Bane Mother, and the Sontarans.
- Title music - Murray Gold
- Music - Sam Watts
- Script consultant - Phil Ford
- Graphics - BBC Wales Graphics
- Director of photography - Tim Knight
- Camera operator - Leon Hoser
- Sound recordist - Olly Astles-Jones
- Make-up - Emma Bailey
- Online editor - Paul Shields
- Dubbing mixer - Ashley Armstrong
- Production executive - Dominic Parry
- Production manager - Jane Jenkins
- Editors - Ivan Probert, Andy Taylor
- For BBC Wales - Brian Minchin, Nikki Wilson
- Director - Pip Banyard
- Executive producers - Gillian Scothern, Russell T Davies
- Series producer - John Piper
- Mr Smith is pleased that Luke left K9 at Oxford when he came home to visit.
- Luke was enthusiastic about helping with the Alien Files, declaring that they don't get enough aliens over in Oxford.
- Mr Smith compares the Sontarans' warlike qualities to that of the Daleks.
Story notes Edit
- This episode established Luke's frequent visits home from Oxford, which he had last been seen leaving home to attend in TV: The Nightmare Man.