Like clockwork, another letter arrived the next morning. Mary watched her papa hand it to Tom and wanted to scream. Tom glanced swiftly over at her before pocketing it with a simple thank you to her father.

Once breakfast was over, Mary went to the office alone, Tom having an appointment in Thirsk that morning. After the events of the previous evening, she fully expected him to continue avoiding her, so she was more than a little surprised when he appeared in the office sometime before luncheon.

'I must confess, I didn't expect to see you here today. I thought you might have decided to give me a wide berth after yesterday,' she said, her pulse tripping as he hung his hat on the rack.

He turned around slowly, gazing at her for a long minute. 'I thought about it.'

'But you obviously decided against that course of action.'

'I decided it was probably better if we talk. Hash this out.'

'Hash it out?' Mary said, raising an eyebrow.

'Yes, because we can't go on like this.'

'All right, then. Let's "hash this out",' Mary said, leaning forward and clasping her hands nervously together on her blotter. She watched as Tom seated himself at his desk, wondering ruefully if he was deliberately trying to put as many physical barriers between them as possible to prevent her accosting him again.

'What you said last night,' he began, looking uncomfortable. 'About not being able to stop thinking about me.'

He stopped talking, his eyes skittering away from her as if he couldn't quite believe he'd said that. Mary waited.

'You didn't really mean that, did you?' he asked, finally managing to look at her.

Mary looked down at her hands, feeling embarrassed, before biting the bullet and meeting his hesitant gaze. 'I did.'

Tom blinked, looking taken aback.

'Did you expect me to say I was only teasing you? Or that I'd woken up and come to my senses?' Mary asked, almost amused by the naivety of that even while she knew this conversation was not going to go well.

'I thought… I thought perhaps you might have reconsidered,' he said.

'Reconsidered? Tom, do you think this is something I've decided to say as a lark? Because it isn't!' Mary retorted, hotly.

'Then what is it if it's not a joke?' Tom burst out, confusion all over his face. 'We've known each other for years now and you've never said anything like this before. Why now? And where is it coming from?'

Mary gazed at him, not sure she had an answer for him.

'I feel like you're playing with me, Mary,' he continued, a note of anguish in his voice. 'Like you're a cat and I'm the mouse you've decided to torture.'

'If I'm torturing you, I'm torturing myself too,' Mary said vehemently, shaking her head. 'Do you think I want to feel like this?'

Tom stared at her. 'Feel like what?'

'Overwhelmed. That's how I feel, Tom. Like I'm drowning in thoughts of you.'

'But I don't understand,' he said, quietly, after a moment's silence. 'I don't understand what's changed.'

'And you think I do?' Mary huffed out in disbelief. 'I didn't ask to feel like this, and I certainly didn't expect it. And it's not like it's convenient in any way.'

Tom regarded her gravely for a moment. 'How long have you been feeling like this?'

Mary considered that, trying to pinpoint when her feelings for her brother-in-law had changed. 'Quite some time, I think. You said yourself I've been obsessed with your correspondence with Miss Smith. So at least since the King and Queen's visit. Although I didn't truly recognise it for what it was until yesterday.'

Tom looked at her curiously. 'Yesterday? What happened yesterday?'

Mary raised an eyebrow at him. 'Don't tell me you've forgotten me kissing you already? Twice. I'm not sure my ego could take that.'

'No, of course, I haven't. But I don't think that's what you were talking about. Something must have happened to prompt you to… to kiss me.'

Mary looked down at her blotter, feeling something bright flare in her chest as she thought back to that first kiss and the overpowering urge she'd felt to do it. She looked up to meet his gaze. 'You were standing there, telling me in no uncertain terms how no highborn woman would ever want you, and it just hit me.'

'What did?'

'That I do. I want you.'

Tom's eyes widened, his mouth dropping open at her bluntness. 'You don't… you don't mean that.'

Mary gritted her teeth in frustration. 'I do. I'm being as honest with you as I can, Tom. This is not easy for me, laying myself bare like this. Please do me the courtesy of believing what I'm telling you.'

'It's just… it's so hard to believe.'

'Is your self-esteem so low that you can't believe any woman would want you?' Mary asked in surprise, wondering suddenly how his years as a widower may have affected Tom. He was not a man she ever thought of as lacking in confidence, but now it occurred to her that maybe he was in his romantic life after so many years alone. Perhaps that was why he was pandering to Miss Smith.

'You're not any woman, Mary,' he replied, gazing across the desks at her.

'No, I suppose not,' she said, pensively, thinking of all the ways they were connected.

'I'm going to ask you something now, but I want you to think about it and not just jump down my throat,' Tom said, looking at her warily.

'Go on,' Mary said, suddenly on her guard.

'The way you've been feeling, did it start when Lucy began writing to me?'

Mary thought about that. 'I think maybe it started when you almost got yourself shot and I had that awful dream, but her letters definitely pulled the matter to the front of my mind. I've been so angry and annoyed about those letters, and with you for being so cagey about the whole thing, but I didn't realise quite why until yesterday when I had one of them in my hands.'

'What do you mean?'

'I'm jealous,' Mary said, simply. 'I'm jealous that she can write to you, that she has your attention.'

Tom nodded slowly, his mind whirring.

'It was a bit of a revelation,' she continued. 'Believe it or not, although I've been obsessing about those letters for weeks, it hadn't even occurred to me that I was jealous until yesterday, but as soon as I realised, it seemed blindingly obvious and now I can't believe I've been so obtuse about it for so long.'

'I don't think you're jealous,' Tom said, cautiously, holding up his hand as Mary frowned at him and opened her mouth to protest. 'No, let me finish.'

He waited until she subsided before carrying on. 'I think perhaps Lucy's letters have shaken you, but not because you have feelings for me like you think.'

'What then?' Mary said, scowling at him. 'Tell me what else can it possibly be? Do you think I am envious of her penmanship?'

'I think you're worried that if Lucy and I become a couple, I will leave Downton. I think that's what's making you feel like this, not that you're suddenly attracted to me.'

Mary stared at him, gritting her teeth. 'You think that's what this is?'

'Isn't it? You're my best friend and I'm yours. I think you're afraid of us losing that close connection if I marry Lucy.'

Panic gripped Mary. 'Are you thinking of marrying her?'

Tom hesitated. 'I don't know. Maybe in time. Although we're not at that stage yet. At least, I'm not.'

Mary swallowed, trying to tamp down the panic and jealousy spiking inside her. 'Are you in love with her?'

Tom was silent as he considered his answer. 'I'm fond of her,' he said, eventually. 'And I'm attracted to her. I could imagine growing to love her.'

Mary stared at him, feeling unwelcome tears well up in her eyes. She blinked, angrily dashing away a rogue tear.

Tom looked alarmed by her getting upset. 'Do you think I could be right? About what's causing you to feel like this?'

Mary continued to stare at him, mulling over his theory. Tom stared back, growing increasingly uncomfortable under her scrutiny.

'No, I don't think you're right,' she said, finally. 'I am afraid she'll take you away from Downton and from me, yes, the thought absolutely terrifies me, but that's not what's at the root of all this.'

'I think it is. I think you're confusing the-'

'Henry made love to me last night,' Mary interrupted without preamble.

Tom snapped his mouth shut, shocked into silence that she should tell him something so private.

'He made love to me and I didn't climax until I shut my eyes and imagined it was you instead,' Mary said, keeping her eyes firmly on Tom even as she felt herself turn crimson.

Tom gaped at her, his own cheeks flooding with colour.

'Can you imagine how it feels to know the most intense orgasm my husband has ever given me came when I pretended he was my brother-in-law?' she asked, relentlessly making her point. 'So, no, I don't think you're right because I know the difference between platonic love and sexual desire.'

He stared at her, completely shocked by her candour. 'You think about me making love to you?'

'I think about you doing things to me that would make a sailor blush,' Mary replied, opting for brutal honesty, and looking him squarely in the eye.

Tom swallowed hard. 'Christ, Mary. You… you can't say these things to me.'

'I'm sorry if I've embarrassed you. I just... I'm trying to make you understand,' she said, awkwardly, her bravado fading, knowing she wasn't handling this very well.

'No, it's not that. I'm not embarrassed. It's…' he stopped, looking down, avoiding her gaze.

'What?' she asked, holding her breath, suddenly dreading what he was going to say as the thought belatedly struck her that he might be repulsed by his sister-in-law having carnal thoughts about him.

He raised his head to meet her eyes, his own simmering with heat, and Mary felt a jolt of excitement.

'It's been a long time since I've… been intimate with anyone,' he said, his voice low almost as if he were in the confessional box.

'Oh,' Mary said, suddenly ashamed that she'd not even thought about that while she'd been busy telling him how she felt when she was fantasising about him while having sex with her husband.

'So, you can't say provocative things like that to me without expecting a reaction.'

She bit her lip, a question burning on her tongue. 'Have you not… since Sybil?'

Tom hesitated for a moment. 'Once. But I was very drunk, and it didn't come from a good place on either side. It was a mistake; one I bitterly regret.'

Mary remained silent, for once at a loss as to what to say, very aware that her sister had been gone for seven long years.

'So, you telling me what you just did, it makes things… difficult for me. Because I don't have the same outlets you do.'

Mary stared at him, her heart tripping, her stomach flipping. 'You mean… it arouses you.'

'What do you think?' he said, his voice dipping into a lower register.

'And you… it makes you want to…' Mary trailed off, unable to voice her meaning as he looked at her intently.

Tom bit his lower lip and Mary watched him, transfixed by it. 'Yes, but that just leads to greater frustration.'

'Because you can't do anything about it.'

'Yes,' he said, tersely.

'But do you want to? Do something about it?' she asked, knowing she shouldn't but unable to keep pushing him towards an admission of… something.

Tom stared at her, naked desire now on his face. 'Let's just say if we were having this conversation and things were different, we might be doing something other than just talking about this.'

She gazed across the office at him, the air between them crackling with tension. 'Tom…'

'Don't. Please.'

'But you're thinking about it too,' she said, softly, almost pleadingly.

'Only because you put the idea in my head.'

'So, you've never… never thought about me like that before? Not once in all these years?'

He hesitated before answering and Mary felt her insides twisting again. 'I'd be a liar if I said I hadn't.'

They stared at each other in silence.

'What are we going to do?' Mary whispered, unable to take her eyes off him.

Tom sighed, closing his eyes briefly. 'Nothing.'

'Nothing?' she echoed, disbelievingly.

'Nothing,' he repeated, firmly.

'But…'

'We… we can't, Mary. We can't do that to Henry.'

'I know,' she said, her shoulders slumping in despair. 'And I know I'm a terrible person for even thinking about betraying my husband. But that doesn't stop me wanting it or thinking about it.'

'But you have to. You have to stop thinking about it – about me – like that.' He paused, shaking his head. 'God, I can't even believe I'm saying this to you.'

'I don't know if I can.'

'You have to,' Tom said again. 'You have to. If it's just lust, it will pass. It has to.'

Mary tilted her head, regarding him carefully, hesitant to say what she knew she had to. 'What if it's not just lust?'

'What?' he said, his eyes going wide.

'What if it's not just lust?' she said again, quietly.

'But it is… isn't it?'

'I don't know.'

Tom stared at her and shook his head slightly. 'No, you're not… what are you saying?'

Mary gazed back at him, screwing up her courage. 'What if I'm in love with you?'

'You're not. You can't be,' he said, completely thrown by her words. He looked at her carefully as if wondering whether she was pulling his leg. 'Are you?'

'I don't know. I know I love you. I have for years now. But what I feel for you is not platonic anymore, Tom, not with the thoughts I'm having. But the love is still there. Does that mean I'm in love with you?'

He stared at her, shocked beyond measure. 'No, no. It's just… these strange thoughts about wanting to... to sleep with me, it's confusing your feelings, that's all. It's a passing phase, a moment of infatuation. You're not in love with me. You're not.'

Mary gazed silently at him.

'You're not,' he said again as if trying to cement the thought in her mind.

'So, what do we do?'

'We ride it out. Try not to think about it and hope these feelings disappear as quickly as they came, and then we go back to how things were between us.'

'So, that's the plan then? For me to stop thinking about you in any way other than as my brother-in-law?' she said, doubtfully.

'Yes. And I'll try to forget everything you've said to me over these last two days. Forget about you kissing me.'

'And you really think that's going to work? Because I have to say, it hasn't worked for me in the slightest so far.'

'It has to, Mary. Because there's no other alternative.'

The sound of the church bells striking noon filtered in through the windows, breaking the silence stretching between them.

'It's time for luncheon. We should go back to the house,' Tom said, a thoughtful look on his face. 'And I think we should stay away from each other this afternoon.'

'You mean I should stay away from you,' Mary said resentfully, feeling like something inside her was breaking.

'No, I mean both of us. You're not the only one this has affected. I need to stay away from temptation too.'

Mary's heart thumped against her ribs as his words sank in. 'Then you are tempted?'

'Of course, I am,' he admitted, quietly. 'But we can't. You know we can't.'

Mary just looked at him, saying nothing, letting her eyes do the talking.

'We can't,' he said again, emphatically.

Mary sighed and stood up, walking over to put her hat on. 'Is this confession going to send you running from me more effectively than Miss Smith ever could?' she asked, sadly.

'No, no, it's not because I care too much about you, Mary. But I think we need to spend some time apart, just for a while until these thoughts and feelings fade,' Tom said, reaching for his own hat. 'Because if we spend almost every day together like we usually do, I think it's just going to get harder for both of us to ignore it.'

Mary bit her lip, blinking back the tears suddenly pricking at her eyes. 'If that's going to be the way it is, can I ask one thing of you now?'

'What?' he said, cautiously.

'Will you kiss me? Just once where you kiss me back instead of pushing me away. Just so I know what it feels like.'

'I don't think that's a very good idea,' Tom said, even as he took a step towards her.

'Please. Just once,' she begged, part of her horrified at how needy she sounded, part of her willing to acknowledge she would prostrate herself on the floor in front of him to have this one thing if she had to.

Tom gazed at her, silently weighing up the wisdom of granting her request.

'After everything we've said to each other today, how much harm can it do?' Mary tried again. 'And is kissing you three times so much worse than kissing you twice?'

Tom hesitated, then moved closer. He took her face in his hands and leaned in, pressing his lips gently to hers. Mary moaned, parting her lips and clutching the lapels of his jacket. Suddenly the kiss went from relatively chaste to something deeper and more desperate on both sides before they broke apart, staring at each other.

'We shouldn't have done that,' Tom whispered, stroking his thumbs over her cheekbones.

'No, probably not. But I'm glad we did,' she whispered back. 'Thank you for indulging me.'

'It was a mistake. It's going to make this harder.'

'It was always going to be hard. I'm not going to be able to simply flip a switch and stop thinking about you. At least I have this memory now.'

'If it's any consolation, I'm going to be thinking about you too now.'

Mary gave him a sad smile. 'Then we're both in a bit of a pickle, aren't we?'

Tom studied her face then released her, taking a reluctant step back.

'If things were different…' he said, his words fading to nothing.

'But they're not,' she said, her voice cracking slightly.

'No.'

Mary took a deep breath, facing facts. 'So, I'll stay at the house this afternoon. Spend some time with George and Caroline. You can have the office. Are you at the dealership tomorrow?'

'Yes.'

'Then I'll take the office tomorrow. We'll have to work out a schedule if we're to stay away from each other. Leave me details of your diary and I'll compare it to mine, see what I can work out about who has the estate office when.'

He stared at her, taken aback by her practicality in figuring out how to make their plan work. 'I'm… I'm going to miss seeing you and spending time with you, Mary.'

He watched as she bit her lip and blinked back tears. 'I'll miss you too.'

They gazed at each other in silence for a moment then Mary gave herself a little shake. 'We should go before they wonder where we are.'

Tom nodded then followed her out of the door. They didn't talk again as they made their way home, each trying to come to terms with what had happened and the deal they'd made.