"If you try to explain, you'll end up telling him about Bletchley... everything."

.

Susan tries to imagine that, travelling home afterwards – telling Timothy everything. On the bus and walking back to her house, Jean's words ring through her mind over and over. Everything. The warning in Jean's voice. Can she imagine Timothy's face, how he might react? The way she had instinctively turned to Millie and Jean's eyes had followed. Of course Jean knew. Jean knew everything, always had. It was her speciality – information, where it was and how to get it, and more particularly knowing all there was to know about everyone she met, because that was so often the key. Information and moderation, those are Jean's watch words. Susan can't be surprised, she thinks as she the bus grunts and shudders its way through weekend traffic.

Timothy would be surprised. There's that look she has noticed once or twice when something has escaped her, an answer too quick, an unseemly excitement over a puzzle. His face gone blank, as if he doesn't recognise her, doesn't know her at all. Horrible thing to have your husband look at you like that. Her heart skipped when she saw it. Her voice stopped. She had looked down at herself to check she was still all there, still the same neat, practical, responsible Mrs Grey she had been before she got carried away.

Oh it is illogical but then people are. Even she is when it comes to emotions and relationships and other illogical people. Puzzles, numbers, systems, mathematics, even words – they all have their logics and patterns. People do to a certain extent but they can't be predicted as easily. That's what makes them even more fascinating, Susan presses her lips together in thought, the combination of order and chaos. Perhaps it's that their patterns are only more complex, far more complex than anything she had worked on at Bletchley. She twists her hands together in her lap to suppress the thrill. If only he could understand that, how it feels to be completely filled up with a puzzle, to have patterns running through her and her whole being working on unravelling them. If only she could explain.

But Susan drops her head and carefully unclenches her fists, deliberately smooths out the soft leather of her gloves, quells the blush in her cheeks, the shame in her chest. She knows she cannot explain this. She is sure these are things she should not feel, and she is not good with words, not good enough to make him understand, if anyone could understand who doesn't feel it themselves. No. She shakes her head. They couldn't. That is one of the reasons she has never spoken of it. That and the Act. Can she bring herself to break it? She signed. She promised absolutely.

Biting her lip, Susan lifts her head and stares out of the window. Half a minute passes before she realises that she is past her stop.

.

On the pavement, she turns back on herself and steps out. Might as well walk it and try to finish thinking it out. Everything. Can she tell him everything? She knows that Jean is right, if she starts explaining she won't be able to stop. Everything is so tangled up together, it's all part of the pattern. One piece doesn't make sense without all of the others. Millie's steady gaze, open and patient as she always is with the big things. It's not fair. She, Susan, is not fair to Millie, but it's the best way she knows how to be. Everything keeps getting more tightly interwound. It's her own fault for bringing Millie into this, searching her out again, making the pattern of her life more complicated. That wasn't her intention, she hadn't been thinking about that at all at the time, it was the pattern of the murders that had obsessed her. But now that that is all laid out bare she can see the places that it connects to other things, to each of them and their broader lives. It's a part of them now. And they are parts of each other even more than they were before – Millie's steady hands on hers, Timothy's morning kiss on her cheek, Crowley's twitching fingers, Lucy's shaking, her fading bruises, Millie's hand on her shoulder, Jean's arm around her, the warning, Timothy's blank look, Lucy remembering- her mind far away, the flickering hurt in Millie's eyes. Everything.

.

She wonders how she will begin, if she is going to tell him. She tries to imagine it.

Darling, there's something I need to tell you. In fact there are lots of things. I almost died today, several times. I put my hands around a live grenade after the pin was pulled out. I was almost murdered. I almost let myself be murdered. For the children's sake. For you. I saw a man die, quite slowly it seemed although it can't have been that long a time but it was slow enough that I could see the moment it happened. I was right. Well, in the end I was right. I solved the puzzle. We did. The four of us. The four of us who were together from the War. From... That's why I got in touch with them actually, I needed their help you see because... because that's what we used to do together – solve things, work things out, analyse and decrypt and decode. At Bletchley. For years. Most of the war actually. We were the ones. Things that made a difference. Things that probably made a difference to you, and your men. It was the most wonderful, gruelling, thrilling time. It was the most alive I've ever felt. Just me and a set of letters or numbers on a piece of paper for hours, days, weeks at a time. Just me and a piece of paper and Millie beside me, sharing the process. Living it. At our desk, in our room. Sometimes it felt like we were sharing the same brain.

.

She is turning her corner now.

I loved it. I loved it all. And the three of them. Millie. We were supposed to go travelling together, we had all these plans. She knew me, she understood me through and through, mind and body and soul. She still does.

.

She is on her own road.

I broke her heart, I think, at least a bit. I know I broke mine. And now I'm breaking yours.

.

There is her house. Her husband, her children, in the window.

She looks back up the street, almost seeing the whole scheme of her words running out behind her, the whole pattern that has brought her here to the moment where she is walking up the path and the door is opening and there they are.

"Hello Mummy."

"Is everything all right? Susan?"

And she is schooling her mouth into a smile and her head is nodding all of its own accord and her lips are pressed tight as she steps forward over the threshold.

.

Behind her, the pattern is already vanishing – easily hidden in plain sight from those who do not have the eyes to see.