Mutant spider (Arachnids in the UK)

The spiders that crawled through Jack Robertson's hotel were genetically modified carcasses that, by toxic waste, revived and grew into enormous sizes.

Hakim Khan usually collected the toxic waste as "evidence" for Yaz.

The spiders were led by a mother spider, who was larger than the others. As it was suffocating by it's own size, Robertson shot it, murdering it. The spiders were eventually contained through the efforts of the Thirteenth Doctor, Ryan Sinclair, Graham O'Brien and Yas. (TV: Arachnids in the UK)