The driver was dressed in some tribal weave. He was unaugmented. There was nothing of the Adeptus Mechanicus about him. He was free-riding, she realised, keeping close to the Baneblades to cut through the convoy.

‘What’s your unit?’

‘Drookian Fenguard,’ the driver said.

‘This is a Cadian convoy. Pull over. You’re going to have to wait,’ she told him.

The driver nodded, but instead of pulling over he surged forward. She had to jump out of the way. Minka cursed.

It took only three single las-bolts before the rear pneumatic tyre burst with a blast of compressed air. Debris shredded off, and then there was the screech of steel rim on the rockcrete road surface.

Minka reholstered her pistol as the Drookians dismounted. There was a captain among them, his Imperial insignia incongruous among his tribal garb.

‘You!’ he shouted. ‘You shot out our wheel?’

She squared off before him. ‘Yes, sir.’

His hand felt for his blade.

Her chainsword was on the Chimera, but she was not afraid. She shifted her weight onto the balls of her toes, ready as he closed the last steps through the gloom.

‘Is there a problem?’ a voice suddenly called out.

It was Colonel Sparker.

‘Look!’ the Drookian pointed. The cargo-8 was listing to the side, the shredded tyre steaming.

Sparker stood between him and Minka. ‘It appears you have a burst tyre. You’re now impeding the road. Please remove your truck.’

The Drookian swore in response. It was a Drookian curse, and the Cadians did not know the words, but the meaning was clear.

Sparker had no time for nonsense. ‘Breve!’ he shouted and signalled the Chimera forward. ‘Please move this rust-bucket off the road.’

There were shouts of alarm as The Saint shunted the cargo-8 forward, dumping the Drookians off the side of the road.

Minka clambered aboard. She felt the Drookians’ hatred as they stared up to watch her pass.

‘I remember you, Cadian!’ their captain called out. ‘We’ll see how your Cadian superiority manifests itself on the battlefield!’

Minka lifted her hand in mock friendship. ‘Not until you get that truck fixed, you won’t.’

The Cadians pushed onwards through what was left of the night. The bleak penal camps were gradually replaced with increasingly cramped cities of flakboard pre-fabs, field-chapels and field-latrines.

Sunrise found them deep within the siege camp. In the grey light of dawn of their second day they passed neatly laid-out munition dumps, watchtowers, sunken armament silos and lifters loading hulking locomotives.