Hosts of the Wirrn

Part one
After the world's strangest interview, UNIT's latest recruit, Shana Siddiqui, hits the ground running to help Osgood with her latest assignment.

The Master left UNIT a parting gift – something alien and deadly. The Wirrn have come to Earth, and now they are free...

Part two
Larvae are hatching. Grubs are mutating. The infection is spreading. As a swarm takes to the skies, UNIT struggles to contain its menace.

Kate Stewart meets the danger head-on. To rid the Earth of the Wirrn, she must now confront their Queen.