Ianto jabs at the button, but nothing happens. "I'm trying! She's changed all the circuits!" He turns to Jack, punching the unit in frustration. "Shut off the power everywhere!"

Jack grabs for the comm link. "Toshiko, cut all power in the base!"

Tosh is still upstairs at the controls. "I do that, the base goes into lockdown! We'll be trapped."

But desperate times call for desperate measures. "Just do it!" Jack orders as Gwen screams again, her eyes fixed on the relentless approach of the machine.

The sound of the newbie's scream echoes through the commlink, deciding Toshiko as much as Jack's order does. She races to the main power switch, yanking the lever downwards, and with a sound like a sigh of relief the machines switch off as the doors swish closed.

All the doors... in all of Torchwood.