It wasn't an experiment. [A pause.] Technically. And things are going exactly as I expected them to be, albeit at an accelerated rate.

[There's another loud THUD, this time against the ceiling. Followed by a series of softer thuds, like the thing is trying to escape by flying up.

Egon slowly removes his hands from the door, glancing towards Venkman.]

You wouldn't happen to have an extra containment unit on hand, would you?