"I am the Light-Hearted Wastelander, daughter of the Pale Adventuress, and I know things that few in London know, and I can do things that none in London can do." 

He nods slowly. "Yes, the child was mine - by Angie. The Fading Music-Hall Singer. She's missing?"

"Yes. What happened to the child?"

"She... she died shortly after she was born. They do that, sometimes. I had refused to claim her - perhaps the fault was mine. The vicar allowed her to be buried on hallowed ground. It was generous of him."

"How tragic, when lingering death is so rare in the Neath...well. As I said, I can do things that none in London can do. Bide a moment, no matter how disturbed you are by what you see."

She plunges her hands into the earth, allowing them to express more of their true adamant nature once out of sight, plowing through obstructions that would halt human flesh, until they reach the tiny coffin. She grasps it and yanks it out, earth spraying to either side as she does so. Opening the coffin lid reveals little more than bones and scraps of leathery desiccated skin. Well. 

She bites her lip, hard, and allows the blood to drip onto her finger. With the blood, she draws a Correspondence sigil on the tiny skull. 

There is a flare of un-Neathly light, and a living babe screams in her arms. 

She holds the child out to their father. 

When she reaches into the earth, his eyes widen. He begins to look angry when she removes the coffin. When she begins her ritual, he looks horrified. Then the child is reborn, and his eyes fill with tears.

"I..." He slowly reaches out, hands trembling, to take the infant. "How?"

"My mother traveled to the Elder Continent, and learned and saw many things there, and when I was born, several months after she left, she taught them to me as well. She cannot do what I can do. Nobody else she's tried to teach can. But death is even less permanent wherever I find it than it is in the rest of the Neath."

"I don't have much to give you," he says slowly. "Not even much information - I'm only an under-secretary. But if you're looking for Angie, you should ask Hephaesta, at Mahogany Hall. They - were, at least - very close."

"Thank you, that's very helpful." She looks at the child. "What's their name?"

"...I don't know," he says. "I wasn't there."

"...Well. I'll find our mutual friend and we'll find out. Thank you again for the information, I'll see what Hephaesta knows." 

She makes her way back to Mahogany Hall and starts looking for entrances other than the main one that seem more likely to lead to performers' rooms.

There are various entrances, mostly guarded.

On the other hand, there are rather a lot of windows on the second floor. Some of which stand open.

She makes her way to a mostly unobserved patch of entranceless wall and climbs to the nearest open second-story window, diamond nails sinking into the relatively soft brickwork.

It leads into a dressing room, currently unoccupied. The mirror is cracked.

What kind of dressing-room? If it doesn't seem plausibly a strongwoman's she'll slip out into the hallway. 

Not a strongwoman's; lots of make-up, and a box of throat lozenges.

The hallway contains a handful of dancers, gossiping amongst themselves. They glance at her as she emerges, but none of them seem to care that she's not the person that typically comes out of that dressing room.

She looks for Hephaesta's dressing-room. 

Well, this dressing room has a little bronze plate on the door reading HEPHAESTA.

Yep, that'd be what she was looking for. She lets herself in and waits. 

After about a quarter of an hour, the door opens and in walks a woman with muscles like grapefruits under her skin.

She notices the Light-Hearted Wastelander and looks her up and down, then sniffs. "Come to ask me where it is? I don't know where it is. Come to kill me? Like to see you try. Come for an autograph? I can do you an autograph."

"Where what is?"

She snorts. "If you don't know, then you don't know, and that's a weight off my mind. Just hand me what you'd like me to sign."

Lucy hands her a scrap of paper. "Thank you--but that's not actually why I'm here. Nobody's heard from the Fading Music-Hall Singer in a while and I'm worried."

Hephaesta relaxes a bit, scrawling her name on the paper. "Well, that's quite an ask. Angie had a lot of friends, so she said, but none of 'em came looking for her, far as I can tell..."

She hands over the paper. "Truth be told, I'm worried for her too. I think she's hiding from something. Something big. But I don't know that you're not part of it, see?"

"Do you know what's buried at St. Dunstan's? The Sensible Under-Secretary can vouch for me."