Now, Adrien and Marinette walk out of the bakery, her face red from crying. Her eyes still wet with tears.

Barry and Lieutenant Roger stand outside.

Barry: What happened?

Adrien: Her mother, she's…

He hangs his head, solemnly.

As Barry's eyes widen, he turns to Lieutenant Roger.

Barry: Let me through, LET ME THROUGH!

Roger: Hold it, I can't let you in there.

Barry: I've studied Forensic science, Lieutenant.
I can identify any clues your guys might have missed.

Roger: I've already had my men go over the house for clues. I don't know what you're expecting to-

Barry: Lieutenant, your men only identified a husband standing over his wife's dead body! You weren't looking for any other clues!

Lieutenant Roger goes to say something, but Barry interrupts him.

Barry: I can identify the composition of the body at the time of death. And establish a credible hypothesis based on the evidence left at the scene. Please, just let me check.

Lieutenant Roger is absolutely stunned at this point.

Roger: Let him through, he's a CSI consultant.

Barry: Thank you.

As he walks in, he dons black isotoner gloves.

Adrien pulls out his phone and calls Nathalie, as he and Marinette walk back to the school.

In the Dupain-Cheng's living room, Barry sets down his bag, and takes out a metal briefcase.
Inside, contains a CSI kit, and tools.

He takes out a mini-flashlight, and scans Sabine's dilated pupils.

Barry: "This wasn't simply a murder. This was a set-up."

He grabs a tube with a cotton swab.
Dabs the cotton underneath Sabine's fingernails.
Puts the swab back into the tube and seals it.

Barry: "Someone was trying to frame Marinette's dad, just like Thawne did with my father."

He grabs another tube, and swabs the inside of Sabine's cheek, and lips.

Barry: "But who would want Marinette's mother killed, just to frame her husband for the crime, and why?"

He takes out a UV light, and scans the room.
Traces of blood specs are illuminated. He collects them.

Barry: "Maybe it's just the CSI in me that wants to be thorough in this. But seeing a mother murdered? That just serves as a reminder of why I became a Forensic scientist."

He finds traces of hair next to the body.

*Barry: "Finally, something I can identify."

He takes a pair of tweezers, and places them in a jar.

Barry then inspects the wound found on Sabine's body.

*Barry: "A deep stab wound, inflicted by a blade.
But none of the knives here, are long or thick enough to cause a wound like this."

He notices something shimmering, in the corner of his eye. He walks over to find a knife, sitting on the kitchen floor.

Barry: Now how did you get out?

He inspects the drawer where the knives were located.
One of them was missing.

Barry: Bingo.