To reiterate what was also pointed out in the definition in Chapter III, you must bear in mind that while the end of each separate reel in an ordinary feature need not end with a forward-looking climax, the end of each episode in a photoplay serial must be a climax of a most thrilling nature, or, at any rate, must be such a climax as will greatly excite the interest of the spectator and insure his coming to the theatre when the next episode is shown.  The serial photoplay is exactly like the well-written and carefully edited serial story of fiction.  Judged from the box-office viewpoint, the supreme test of a good photoplay serial is its ability to keep the same spectators coming to the theatre where it is being run week after week.

What has been said as to the thrilling climax at the end of each episode, or chapter, must not be interpreted as meaning that a mere thrilling situation is all that is required.  In the boys’ story-papers of a few years ago, referred to in our discussion of the cut-back, the hero was frequently left hanging over the edge of the cliff, or tied to the railroad track, or waiting for the timed fuse to reach the keg of powder.  These situations in themselves were sufficient to make juvenile readers wait anxiously for seven whole days in order to find out what would happen “in our next.”  It has been demonstrated, however, that what holds the attention of the photoplay spectator, young or old, is the mystery connected with the story, and it is the solving of this mystery that must constantly be kept in mind.  “Who is the masked stranger?” “Who is the owner of the mysterious clutching hand,” “Who is the mysterious and ominous personage who inevitably sends a telephone message of warning when about to strike down a new victim?” These are the questions that keep them guessing from week to week and draw them back to witness every episode.  Your climax may be a thrilling situation—­should be, in fact—­but it must also be a definite way-station on the journey to the point of discovery.

While there is still a great deal of absolute nonsense—­viewed from any standpoint of common sense and logic—­in most photoplay serials, and while the long-drawn-out mystery is often made possible only by the introduction of weird and unnatural happenings not even possible in real life, there is now a tendency toward serials more true to life and more dependent for their success upon plots that will stand the acid test of logical reasoning.  The very fact that each separate episode, with its various situations in the working out of the mystery, had to be depended upon to draw the crowds back again to see the next episode, was taken as sufficient excuse for the introduction of situations that would make the wildest exploits of “Diamond Dick” or “Old King Brady” read like the Sunday-school stories of a generation ago.