New characters introduced late

It has happened more than once that a new character is introduced at the same late period. In The Lady from Oklahoma, three char¬acters were introduced after the out-of-town open¬ing. So you see how broad must be the rule to have your characters well in mind from theginning. Their individuality must in no way prevent your deletion of one or several, nor your supplanting of any with another and totally different personality. Characters suited to necessary actions. If you wish a certain act committed or a certain situation created, you must devise a character or characters which would under the circumstances bring those events to pass. You cannot outrage the probabilities by making your people do things which would be utterly contrary to the personalities you have shown. This is so important that some writers go to consid¬erable lengths in making sure that the character is in every way consistent. One writer takes a long sheet of paper, and on this he traces back the geneal¬ogy of his imaginary hero—his birthplace, his par¬ents' names and characteristics, their birthplaces, and so on—until he has to his own satisfaction created progenitors and environment that would have brought forth his character.