us at any time'
'Jolly good,' grinned the Doctor, shutting his eyes and sipping bravely at his tea.
A few minutes later Walters returned with a compact object resembling a small pocket torch.
'Here you are,' boomed the Brigadier cheerfully, pressing a button to spring a short aerial out of the end of the device. 'It's on a fixed frequency. Range about a hundred kilometres. Just press the button and ask for me.'
'Splendid!' cried the Doctor appreciatively, draining his mug with a last heroic gulp. 'As long as it doesn't play rock and roll it will come in very handy,' he added glancing severely at Jamie who was already on his feet and raring to go.
Lethbridge-Stewart stood up briskly. 'Well, Doctor, if you're determined to conduct your own investigation I'd better organise a chopper to take you back to London. Some more tea before you go?'
The Doctor leaped out of his chair as if he'd been stung. 'No, thank you,' he replied in a strangled voice, snatching up the polyvox unit. 'Perhaps some other time, Brigadier...'
Zoe and Isobel stood nervously between two armed security officers in front of Vaughn's desk, while Packer hovered shiftily in the background.
'You and your friend the Doctor have put me to considerable inconvenience today,' Vaughn purred. 'First he breaks into the building and now you ruin a rather expensive installation.'
'Only because it refused to answer our inquiry,' Isobel retorted.
Vaughn smiled. 'You are naturally concerned about your uncle, Miss Watkins, but I can assure you that he is perfectly well, if a trifle uncooperative at the moment. Indeed, your visit is most opportune.'
'Why?' Zoe demanded warily.
'The Professor needs to be encouraged to continue his invaluable work for us,' explained Vaughn blandly.
Isobel shrugged. 'I can't persuade him to do anything.'
Vaughn leaned forward. 'No, but I can. Now!' he murmured icily.
The girls shivered slightly as they heard Packer sucking air through his crooked teeth in eager anticipation.
'Mr Packet will take care of you while you're here,' Vaughn told them, nodding to his Deputy. 'He enjoys showing visitors round our facilities.'
Packer grinned hideously. 'It will be a pleasure,' he promised, as the guards seized their captives by the arms and propelled them out of the office.
'Oh, Packer.'
Packer turned round to find his master gazing at him with amused concern. 'Yes, Mr.Vaughn?'
'Don't work too hard, will you?'
Once again the Doctor and Jamie found themselves staring with sinking hearts at the number 13 on Professor Travers's front door, while the bell rang monotonously inside.
'Och, they must've gone out,' Jamie sighed despondently.
Delving into his pocket the Doctor unearthed a small penknife bristling with different sized blades and all manner of attachments.
Selecting one, he deftly poked it around in the lock and a few seconds later the door clicked open. They went in, calling and whistling, but the house was silent.
In the studio they came across the remains of the sardine sandwiches. 'I don't know what they are but I'm ravenous!' cried the Doctor, biting greedily into two thick portions at once.
'Sardines!' Jamie cheered. 'Delicious, I'm fair starved.'
They finished the leftovers in silence. Then Jamie took out his transistor and a deafening rock number suddenly blared out, causing the Doctor to choke on his last mouthful. Snatching it away from Jamie, he was about to fling the offending device into the grate when he changed his mind, switched it off and opened the back instead.
'Och, dinna wreck ma wee gift,' Jamie pleaded indignantly.
Ignoring him, the Doctor took out a watchmaker's eyeglass and carefully scrutinised the inner surface of the plastic lid. 'Most ingenious...' he muttered after a while. but I wonder what it's for?'
'What what's for?'
'There's a micromonolithic circuit etched into the back of this casing, Jarnie.'
'Aye, and what's that when it's at home?'
'A hyper complex miniature array,'