Re-reading the Lord of the Rings, Chapter 16

Gandalf directs the show, and everybody knows.

It starts at Durin's Doors. Gandalf can't figure out what to say, although, or shall we rather say because?, the riddle on the wall could be solved by any Hobbit.

Boromir complains about his antics, and Gandalf confesses to them.

‘The answer to your first question, Boromir,’ said the wizard, ‘is that I do not know the word – yet. But we shall soon see. And,’ he added, with a glint in his eyes under their bristling brows, ‘you may ask what is the use of my deeds when they are proved useless.’

Boromir gets tired of this and throws a rock into the water, and lo and behold, Gandalf comes upon the right answer.

Already before, after Gandalf had Aragorn successfully maneuvered into coming with him to Moria, Aragorn tells Gandalf straight to his face that he knows what Gandalf has in stock for him.

You followed my lead almost to disaster in the snow, and have said no word of blame. I will follow your lead now – if this last warning does not move you. It is not of the Ring, nor of us others that I am thinking now, but of you, Gandalf. And I say to you: if you pass the doors of Moria, beware!

The next time Gandalf doesn't know what to do there is a well nearby, and although Pippin really doesn't want to do it, there seems to be some other will that is pulling him towards it

Pippin felt curiously attracted by the well.

and then gives him the idea to throw a stone down into it.

Moved by a sudden impulse he groped for a loose stone, and let it drop.

The result of which is that Gandalf can't take the level path now, now that there are drums in the deep, but has to lead the Company up, far above the Great Gates. And there, after the Company camped in the great halls of the dwarves, it is vitally important for him to show them something before they continue on the way that everybody, or in any case Boromir, knows to be the way down to the Gates.

‘Which way shall we take? Yonder eastward arch?’ ‘Maybe,’ said Gandalf. ‘But I do not know yet exactly where we are. Unless I am quite astray, I guess that we are above and to the north of the Great Gates; and it may not be easy to find the right road down to them. The eastern arch will probably prove to be the way that we must take; but before we make up our minds we ought to look about us. Let us go towards that light in the north door.’

And there they find Balin's tomb, getting at least Gimli into the right mood for love-making.

Puff-puff.