She walks slowly, but not so slowly as to be noticeable.
Her feet stick to the pavement, but there's no chewing gum on it.
Lydia's head is down, her eyes swivel from side to side, and she shrinks in on herself, trying to seem smaller and greyer to match the buildings nearby.
Her heart thud-thud-thuds in both ears, and her eyes concealed behind the regulation spectacles are fixed on the group of children moving in their carefully observed groups, doing a strange new dance that a government expert has recommended.
Pulling her hood forward over her thin face, she checks around to see if anyone is watching her.
The railings pull her hands, and her hands close over them and clench hard. Teeth clenched too, she spots him circling in the nearest group.
The sensor has started out of its housing to make a sweep, but her hands won't let go.
Her teeth grind.
Her arms ache.
The boy with the hair that no one can tame falters in his strange dance and glances towards the grey-faced woman with claw-like hands clinging to the thick iron bars.
"Johnnie," she breathes. "Johnnie."
With gun unholstered, the second security guard is running across the astro-turf towards her. His knuckles are white as they tighten on his gun.
The other guard races up to her. "What are you doing? You have no clearance to be in this area."
Although she seems to be looking in his direction, Lydia is really staring past him at the small boy with the blond hair. "I - I was... going..."
The other guard checks the monitor in his hand. "It's Mrs. Malham, isn't it? 209 Bayswater Drive. Widow of Clarence Arthur George Malham..."
"Yes," she answers quietly, then she shouts, "Johnnie! JOHNNIE!"
The guards are surprised, then they take hold of her knuckles and attempt to bend her fingers back to remove her thin fingers from the bars. "JOHNNIE! IT'S MOTHER! JO..."
One of the guards hits her hands with his nightstick. Her fingers are numbed and fall away; her hands flop to her sides. The boy stands uncertainly in his pose, wondering what to do. Someone called his name. Should he answer her?
He doesn't know.
Lydia's tears are raining down her face as the boy hesitates in his circle, and the other children begin to slow and stop to watch him watching the thin grey woman outside the fence.
"Johnnie," she says on a sob. "Joh..."
The nightstick rises again. Her fingers leave the bars and her eyes fill again.
The boy is persuaded to move off with his group towards the grey building. He doesn't look back and he hunches his shoulders as if trying to shake away the image of the grey-faced woman beyond the bars of the fence.
"Go along now, Mrs Malham. We'll have to report this behaviour, you know. We can't have this sort of thing happening. I'm sure you realise..."
Her head lifts inside the hood, and, for a second, her eyes kindle. The guards step back. "I realise..." she says softly. "I realise..."
Her steps are leaden as she walks away back where she came from.
"Who was she?" says the second guard to the first.
"Oh," the other man answers, "Just one of those crazy home educators. No one to worry about at all. She can't do anything... Got no power."
The second guard watches the bent grey back for a moment more. "I feel sorry..."
"Don't say it!" The first guard shakes his head. "Don't say it. You don't know who's listening."