It occurs to Castle as he's looking down at her upturned face, her lips parted and cheeks full of colour, that detective Kate Beckett should be open to using the power of her green eyes in the interrogation room. Mob bosses, drug lords, human traffickers -- they'd all capitulate within the first five minutes if she gave them the look she was giving Castle now. He feels his stomach drop an octave.

"I should probably go," he murmurs, the statement half lost in the wake of Tyler's reedy crooning.