Tegan and Nyssa. 'Get everyone into the TARDIS immediately!' he shouted, crawling painfully back over to the hatchway.
Tegan and Nyssa hesitated for a moment. Then, yelling to the troopers to follow them, they set off hurriedly towards the tunnel.
Adric grabbed the Doctor's shoulder and tried to drag him away. 'Come on, Doctor. You can't stay here,' he insisted.
The Doctor shook himself free. 'It was my own stupidity that set this thing going, Adric,' he retorted, 'and the least I can do is try to stop it.' The Doctor poked frantically about inside the compartment, while Adric looked on in mounting horror.
Scott had been vainly trying to contact Trooper Walters, but his radio produced nothing but a weird oscillating whine. Suddenly the Doctor whipped round and listened for a second or two. Then he thumped himself on the forehead with his fist. 'Of course!' he cried, leaping to his feet and seizing Adric by the arm. 'Come on you two!' and he ran off at breakneck speed towards the TARDIS.
The Cyberleader emitted a vicious, stabbing hiss as a shrill warning siren began to howl from the control module. The Deputy examined the instruments blinking in the gloom.
'The Earthlings have succeeded. They have penetrated the bomb cell, Leader.'
The towering figure waved his arm dismissively. 'The Earthlings are too late.
Priming sequence has been initiated?'
'Then how much longer until detonation?'
'Sixty seconds, Leader. Neutron exchange approaching optimum,' the Deputy reported.
'Excellent,' the Leader replied with a soft, gaseous hiss. He removed a kind of key from his belt and inserted it into a socket on the module. Then with a rasp of satisfaction from his ventilator grille he twisted the key sharply back and forth several times. 'Master detonator released. Proceed to detonation.'
'Affirmative. In fifty-five seconds from now, Leader.'
In its cell deep underground the bomb buzzed and flashed with increasing power in obedience to the signals pulsing across the solar system...
'Set all co-ordinates to zero!' the Doctor yelled to Adric who was close on his heels as he rushed into the TARDIS control chamber. Then he ducked under the central console, snatched open a small panel set into the pedestal and rummaged about inside.
'It would be nice to know exactly what you're up to, Doctor,' Adric remarked resentfully as he carried out the Doctor's instructions on the main console.
The Doctor pulled out a tangle of brightly coloured cables, frowned, shook his head and thrust it back again. 'The bomb is being armed by remote control...' he explained, pulling out another knot of wires and feverishly trying to untangle them.
'So you could jam it!' Adric suggested eagerly.
'Yes, once I know where its getting its orders from,' the Doctor said, making a few rapid reconnections.
At that moment Scott, Kyle and the troopers entered and stood in awed and astonished silence, staring round the spacious interior of the narrow, shabby old police box.
The Doctor jumped up and flicked a few switches on the console. 'That can't be right!' he frowned. 'Or can it?'
'How long does the arming procedure take?' Adric asked nervously while the Doctor dithered about, bobbing up and down from console to pedestal and back again, muttering secretly to himself.
'Not long,' he replied brightly, totally engrossed in his task.
'Well . . . can't I help at all?' Adric demanded. The Doctor did not reply. Adric glanced worriedly at Tegan and Nyssa.
'Shouldn't you move the TARDIS, Doctor?' Tegan asked timidly. 'Before that bomb thing goes off?'
After a few more seconds silence the Doctor jumped up and again checked some instruments on the console. 'We must hurry!' he cried, yanking a kind of drawer brimming with a strange assortment of tools out of the pedestal.
'You've managed to jam the signal?' Nyssa asked hopefully.
'Temporarily. If they increase power they can easily break through again...'