Something like that gaggle of spooky laughter approaching from round the corner right about now? Jack's just opened his mouth to agree that clearly they have something major they both agree on - how amazing Ianto is - when he hears it and changes what he was going to say abruptly. "How are you with the wasps?" he asks urgently, in an echo of his first question, as he simultaneously draws his gun and bends to pick up his discarded knife.
He hasn't had so much success with the wasps so far, himself.