Everything in the room gets cold, fast.

It's one thing to put pictures on a television screen and understand that his friend, his colleague had intimate dealings with a group of people getting picked off one by one, but it's a whole other to see the toll the case is obviously taking on her. He feels some of his anger, some of his betrayal fade away in the face of it.

No matter how he feels about Emily keeping secrets, secrets she's obviously still keeping, at least from him (and he's trying not to feel the additional sting of betrayal that Hotch obviously knows) he can't imagine what it would feel like to stand by while his team is picked off one by one. Or at the least he's impressed with her self-control. He can't stay he'd still be here in her position.

He's not stupid enough to think she couldn't hunt Doyle on her own if she wanted. The one thing Derek knows for sure is that there isn't a member of this team that wouldn't put everything on the line if it meant the lives of their found family. There is a dark side in each of them, one they have no problem justifying if it's one of their own at risk.

"I'm coming with you."

It's a bad idea. It's a terrible idea and Derek doesn't even have to glance at Hotch to understand that his boss is whole-heartedly against the idea. So naturally, Derek looks at the woman devastated and half-collapsed against Hotch and says, "Let's go."

She's silent for the drive, looking out the window and chewing her nails. He's familiar with the habit, but where he'd usually reach over, slap her hand away, he merely grips the steering wheel.

"I wish you'd told me," he says quietly. He's been trying so hard not to take it all personally, the fact that she hadn't said she's in trouble when Doyle had shown up, hadn't immediately come to him, to them. He can't help wondering if her friend would be alive, how many members of her team, how many people, would still be alive if she'd only said something sooner.

"How?" she asks. "It's not like a happy childhood story or a funny anecdote from my teenage years. It's…"

He gets the immediate sense that she's not totally sure how to explain what are likely to be complex emotions. He's never known her to apologize for actions she saw as right, as necessary, and from the emotions skittering across her face he concludes it's exactly that. Pride but also hurt, self-loathing and the wish that maybe things had gone a little differently.

"You're in danger," he finally says.

"It's not the first time," she points out sharply. "I don't need you to protect me."

He grips the steering wheel again, his fingers flexing and releasing on the leather. She is stubborn and headstrong, always has been, but this. This. This is her life. Can't she see that?

"It's not about protection," he finally manages to say without feeling like he wants to shake her. She snorts in disbelief before he can go on and he takes the time to glare at her. The defiance in her eyes hurts, maybe more than it should. He's mature enough to admit that to himself, even if he'd never say it to her.

"Dammit, Em. You're not alone. You're not."

"Neither were you."

He's smart enough to know what she's talking about and has known her long enough to recognize when she's lashing out. She's always been good at cutting someone down at the knees.

"How do you think I figured it out?" he finally says, when he knows he won't say something he'll regret. "Let us help."

Let me help.

Her shoulders slump, he sees it out of the corner of his eye, but he feels no corresponding triumph. She's still closed off, still defensive and separate. Impotence rises up in him, tart, sharp and metallic in his mouth.

She confirms the feeling when she says, "This is my mess. And I'll be damned if I let one of you get killed trying to clean it up."

Instead of responding, he parks. Instead of reaching out, shaking her, snapping her head off to try and see sense, he lets her lead the way up the stairs, following the flow of officers. Which means he's there, right there, to see the way her face goes white when she sees the body in the hall, see the way her hands shake before she takes a deep breath and centres herself.

He vows then and there that he will not let her run. He will not let her do this alone because he'd tried. He'd failed then and he's never been so grateful for a failure in his life.

He will not let her make the same mistake.