Tony stops immediately at the sound in Donatello's voice. Something is wrong.

He turns to look and see's what Don is looking at.

"Wait a tick, is that....."

A goddamn geiger counter?! Yes. He doesn't even need to finish the question to know that, and he doesn't have to be told twice why one of those might be laying around here. Couple that with the mess around this place, he almost feels a fool not having figured it out already.