9/10 Now up to speed, Mike Yates joins forces with the Time Lord to tackle the alien swarm.
8/10 The Time Lord concludes his tale of encountering the deadly insects in medieval England.
7/10 In his next alien insect encounter, the Time Lord travels back to medieval England.
6/10 The Time Lord concludes his tale of battling alien bugs in a 19th-century big top.
5/10 The Time Lord re-encounters the alien swarm in early 19th-century rural England.
4/10 The Time Lord concludes his tale of the alien-infested ballet pumps in 1930s Cromer.