The Unexpected Guest by Agatha Christie

called MacGregor - ' she told Julian. She gave him a desperate look, pausing to allow him an opportunity to make some comment.
    'Well, that's all right, then,' he replied. 'They'll probably go on thinking so.'
    'But suppose -' Laura began.
    Farrar interrupted her. 'I must go,' he said. I've got an appointment.' He rose. 'It's all right, Laura,' he said, patting her shoulder. 'Don't worry. I'll see that you're all right.'
    The look on Laura's face was one of an incomprehension verging on desperation. Apparently oblivious of it, Farrar walked across to the french windows. As he pushed a window open, Starkwedder was approaching with the obvious intention of entering the room. Farrar politely moved aside, to avoid colliding with him.
    'Oh, are you off now?' Starkwedder asked him.
    'Yes,' said Farrar. 'Things are rather busy these days. Election coming on, you know, in a week's time.'
    'Oh, I see,' Starkwedder replied. 'Excuse my ignorance, but what are you? Tory?'
    'I'm a Liberal,' said Farrar. He sounded slightly indignant.
    'Oh, are they still at it?' Starkwedder asked, brightly.
    Julian Farrar drew a sharp breath, and left the room without another word. When he had gone, not quite slamming the door behind him, Starkwedder looked at Laura almost fiercely. Then, 'I see,' he said, his anger rising. 'Or at least I'm beginning to see.'
    'What do you mean?' Laura asked him.
    'That's the boyfriend, isn't it?' He came closer to her. 'Well, come on now, is it?'
    'Since you ask,' Laura replied, defiantly, 'yes, it is!'
    Starkwedder looked at her for a moment without speaking. Then, 'There are quite a few things you didn't tell me last night, aren't there?' he said angrily. 'That's why you snatched up his lighter in such a hurry and said it was yours.' He walked away a few paces and then turned to face her again. 'And how long has this been going on between you and him?'
    'For quite some time now,' Laura said quietly.
    'But you didn't ever decide to leave Warwick and go away together?'
    'No,' Laura answered. 'There's Julian's career, for one thing. It might ruin him politically.'
    Starkwedder sat himself down ill-temperedly at one end of the sofa. 'Oh, surely not, these days,' he snapped. 'Don't they all take adultery in their stride?'
    'These would have been special circumstances,' Laura tried to explain. 'He was a friend of Richard's, and with Richard being a cripple -'
    'Oh yes, I see. It certainly wouldn't have been good publicity!' Starkwedder retorted.
    Laura came over to the sofa and stood looking down at him. 'I suppose you think I ought to have told you this last night?' she observed, icily.
    Starkwedder looked away from her. 'You were under no obligation,' he muttered.
    Laura seemed to relent. 'I didn't think it mattered -' she began. 'I mean - all I could think of was my having shot Richard.'
    Starkwedder seemed to warm to her again, as he murmured, 'Yes, yes, I see.' After a pause, he added, 'I couldn't think of anything else, either.' He paused again, and then looked up at her. 'Do you want to try a little experiment?' he asked. 'Where were you standing when you shot Richard?'
    'Where was I standing?' Laura echoed. She sounded perplexed.
    'That's what I said.'
    After a moment's thought, Laura replied, 'Oh -over there.' She nodded vaguely towards the french windows.
    'Go and stand where you were standing,' Starkwedder instructed her.
    Laura rose and began to move nervously about the room. 'I - I can't remember,' she told him. 'Don't ask me to remember.' She sounded scared now. 'I - I was upset. I -'
    Starkwedder interrupted her. 'Your husband said something to you,' he reminded her. 'Something that made you snatch up the gun.'
    Rising from the sofa, he went to the table by the armchair and put his cigarette out. 'Well, come on, let's act it out,' he continued. 'There's the table, there's the gun.' He took Laura's cigarette from her, and put it in the ashtray. 'Now then, you were quarrelling. You picked up the gun - pick it up