'Well, yeah, that'd be good,' said Martha. But she had been with the Doctor long enough to know a trap when she saw one. 'Why are you so keen to get me into this cocktail lounge?'

The robot had a smooth, expressionless face and yet still contrived to look guilty. 'I apologise for any perceived subterfuge, Ms Martha,' he said.

'And if I refuse to go with you?'

'Checking,' said Gabriel. 'The regulations state that our first priority is our passengers' safety. So in such an instance I would be authorised to escort you by force.'

'I see,' said Martha. 'So I don't really have any choice, do I?'

This didn't seem to have occurred to Gabriel. 'Checking,' he said. He checked for a moment and then admitted dourly, 'No, Ms Martha.'

Martha tried to remember the route as they made their way to the cocktail lounge. They turned left, left again and then right, and then made their way up a wide staircase. The ceilings were higher on this new level but it still felt cramped and claustrophobic.

Gabriel led Martha into a lavish ballroom, a vast space after the narrow corridors, but still small and claustrophobic. Loud and laughing voices came from somewhere beyond.

Two rows of slender columns divided the room in three. The columns, reaching from floor to ceiling, suggested that such a wide, open space threatened the integrity of the ship. Martha had already learnt that space travel was never as glamorous and clean as it looked on telly. Yet when the Doctor had told her about the Brilliant before, she'd imagined something slightly less difficult. Something glamorous and a bit posh. This was more like a rickety old crate with nice carpet.

Another robot packed up tables and stacked them in a corner; Martha had clearly missed dinner. It all just got better and better.

Gabriel did not seem to acknowledge this other robot as he led Martha past. She resisted the urge to help with the tables. But as she crossed the room, she could see the carpet glittering with broken glass. Now she looked, one of the tables had been smashed apart, too; the robot stacked broken pieces. Again, the robots declined to acknowledge whatever had happened. Martha felt a sudden need to run, though she knew she had nowhere to go. Besides, the voices coming from the next room sounded lively and friendly.

Beyond the ballroom, and through a discreet door, the small cocktail lounge awaited. Her nostrils flared at a sudden tang of oranges and lemons. For a moment she thought the lounge must be perfumed, but as she stepped through the door she realised the sweet stench came from the tentacled aliens.

There were maybe a dozen of them, tubby, egg-shaped creatures, either all-orange or all-pale-blue. They crowded around the great bay window, looking out onto twinkling stars. Martha realised they were right at one end of the ship, where the passengers could sip elegant drinks and admire the view. Their ball gowns looked expensive and floaty, and they wore lots of heavy jewellery all down their long and nimble tentacles. Martha watched them busy with chatting and drinking, and ignoring her arrival. For all she couldn't name the species, she felt like she must have seen them before. And then it struck her: it was like going to a party with Mr Tickle's family.

'Hello!' she said brightly, like her sister did at parties. The aliens stopped talking to look at her. There was a sudden, horrible silence.

'Er . . .' said Martha. She hated being the centre of attention. And these aliens had big, staring eyes. It didn't help that she knew their posh party through the stars depended on those sorry, mouthless men, slaving away downstairs.

'Might I get you an aperitif, Ms Martha?' said Gabriel. The party of aliens clearly took this to mean they could carry on with their urgent conversations. Martha was again ignored. She couldn't thank Gabriel enough.

'That'd be nice,' said Martha. 'What have you got?'

Another robot manned the long bar on one side of the lounge. The menu offered all kinds of brightly coloured drinks that Martha had never heard of. The only thing she recognised on the list was 'hydrogen hydroxide' – or water, as they called it back home. Martha could have it in a glass, in a bowl or in an 'immature Mim'. She thought she could live without knowing exactly what that last one was.

She sipped her water, feeling under-dressed in her jeans and vest-top, and terribly tall and awkward around the dumpy aliens. It was no fun being so noticeable at a party; it made her all self-conscious. She just wanted to be invisible. Slowly, Martha made her way to the great bay window and looked out into the darkness beyond. The stars seemed tiny, so distant that she couldn't tell if the ship were moving towards them or away. Perhaps one of those tiny pinpricks of light was her own sun. Or perhaps she was too far from home even for that. She would never get used to that feeling.

'And what do you make of it all, dear?' asked an orange alien beside her, so suddenly Martha spilt her glass of water.

'Oh, I'm sorry,' said Martha, feeling even more stupid as other aliens turned to look at her.

'No, no,' said the alien, kindly. 'We're all a little unnerved. I'm Mrs Wingsworth. My friends call me Mrs Wingsworth.'

'I'm Martha,' said Martha, holding out her hand.

Mrs Wingsworth peered at it suspiciously. 'Is there something the matter with your paw?' she asked.

'No,' laughed Martha. 'It's a custom on my planet. We shake hands when we make friends.' She slowly reached for the tip of Mrs Wingsworth's right tentacle and showed her how it was done. The tentacle felt rough and wrinkled, like an elephant's trunk.

'How marvellous!' laughed Mrs Wingsworth. 'I must remember that for my brother. He's a great enthusiast for primitive cultures.'

'My pleasure,' said Martha, though she didn't feel it. Last time she'd been so patronised she'd been washing floors in a school. 'So what are people unnerved about? Is something going on?'

'My dear!' said Mrs Wingsworth, wrapping a tentacle around her in what Martha realised was meant to a friendly manner. 'I'm afraid,' said Mrs Wingsworth gleefully, like this was such an adventure, 'that our vessel has been invaded!'

'What?' said Martha. 'By who?'

'By,' teased Mrs Wingsworth, taking her time to explain, 'aliens! It's thrilling, isn't it?'

Martha wished she had asked for something stronger than a glass of water. Of course there'd be an alien invasion somewhere. There always was when the Doctor showed up.

'What kind of aliens?' she said.

'You'll be able to see in a minute. They're making their way down here. Probably want to kill a few of us!' Mrs Wingsworth seemed to find the whole thing delicious fun.

Martha extracted herself from the long orange tentacle and made her way over to Gabriel. 'Has the Brilliant been invaded?' she asked the robot.

'I'm afraid so, Ms Martha,' said Gabriel. 'They gave orders that passengers should all remain in this room, and that they would kill anyone who left it.'

'That's why you brought me here, then?' Martha asked Gabriel. 'It was for my own safety.'

'Indeed, Ms Martha.'

'Oh, we'll be perfectly all right, dear,' said Mrs Wingsworth. 'So long as we do as we're told.'

'But Gabriel! The Doctor will walk right into them,' she said. 'The bloke I was waiting for, I mean.'

'I shall return to the engine room and intercept him,' said Gabriel. 'Please do not worry yourself, Ms Martha.'

He turned to go, and Martha ordered a refill of water from his colleague behind the bar. A gasp of excitement from the other passengers made her turn quickly round.

Three burly, humanoid spacemen stood in the doorway to the cocktail lounge, chunky-looking guns in their hands. Their faces were hidden by dark, domed space helmets. A skull and crossbones had been crudely painted on the chests of their battered spacesuits: they were pirates.