Mother spider (Arachnids in the UK)

The mother spider was a large spider who grew because of toxic waste dumped at Jack Robertson's hotel.

Eventually the mother spider became so big it began to suffocate as it could not absorb enough oxygen, even in a ballroom inside the hotel. When the Thirteenth Doctor, Yaz, Ryan, and Graham with Dr Jade McIntyre went to deal with it, they realized it was dying anyway, and Jade stated the spider was more afraid of them than they were of it.

Robertson shot and killed it, much to the anger of everyone present. (TV: Arachnids in the UK)