The Doctor hit a button on the console, and two white blobs stood out in a field of static. ‘Yes! We’re all good.’

‘What if they fall off or conk out?’

‘Not a chance. These tags are conflict-grade life-beacons used by the Hondopel Peace Corps in search and rescue expeditions across the battlespaces of the Andromeda galaxy.’

Graham raised his eyebrows. ‘You mean, they’re basically army surplus?’

‘I mean they can only be deactivated by the wearer inputting the proper code.’ The Doctor gave him a reassuring smile. ‘To remove one by force is considered a war crime. You don’t mess with the Hondopels.’

‘But won’t these Honda-things come looking for him?’

‘I tweaked the signal so it’s sending out on unofficial frequencies,’ she said smugly.

‘OK, but you know how clumsy Ryan can be,’ Graham persisted. ‘What if the beacon gets damaged?’

‘They’re designed to withstand practically anything. Laser blasts, radiation, cellular disruption, alien mucus … even your bog-standard explosion—’

A noise like thunder rumbled through the twisted fleshy walls. Both the Doctor and Graham were thrown to the sticky floor as a savage blast shook the station.

Graham groaned, rolling onto his back. ‘Explosion, you say?’

‘I wish I hadn’t.’ The Doctor was back on her feet, quick as a cat. ‘Speak of an explosion and an explosion appears! That’s the old saying, isn’t it—?’

Another giant impact flung her forward, face-first into the side of the TARDIS. Graham felt the floor flex beneath him and then buck him to his knees as the aftershocks tore through the infrastructure. ‘It’s “Speak of the devil”,’ Graham shouted.

‘It’d better not be him again,’ the Doctor muttered.

A horrible hooting noise ripped through the room. Graham clutched his ears, not sure if this was some sort of siren or the station itself screaming in pain.

‘Get on to Will, see what’s happening,’ the Doctor shouted over the din, fingers flickering over her console. ‘I’ll see if Squidgy here can pull up an external feed …’

‘Gotcha, Doc.’ Graham scrambled up, dived back through the TARDIS doors and threw himself onto the communicator. ‘Will, what the hell! We’ve been hit twice. Thought you had eyes on us, mate? Over!’

‘Nothing’s been launched from down here, Graham.’ Will’s calm voice carried over the speakers. ‘Whatever’s hit you, it came from space. Nothing’s showing on radar. Other scans running now. Over.’

Graham waited tensely, cold sweat inching down his back.

‘Mass anomaly detected together with two huge radiation spikes. Looks like some kind of spacecraft just opened fire on you and it’s closing fast.’

‘Over,’ Graham breathed, in unison with Will. The wailing noise from outside suddenly stopped, leaving only the sickly background hum of the station systems, edged now by a catching, skittering note. He turned and ran back outside.