psychological tension

The conjecture was at least a plausible one, and the detective began to seriously regret that he had embarked on the affair. As for Captain Speedy, he continued to howl and growl in his cabin; and Passepartout, whose duty it was to carry him his meals, courage...

He grew very grave; and, after thinking the matter over for a while asked me to take him to Renfield. As we came to the door we heard the lunatic within singing gaily, as he used to do in the time which now seems so long ago.