Is the plot in the play J. B., by Archibald MacLeish, climactic or episodic?
The plot in J. B. is not episodic. It is climactic. An episodic plot structure is one that consists of a series of loosely related stories. These may have one structural element in common that loosely relates them one to the other. It may be a structural element of a common place, theme, or character. Other than the one structural commonality, there is no other connection between one episode and the next in an episodic structure.
A climactic plot structure, on the other hand, is a structure in which all scenes or chapters are causally or otherwise directly related to each other. The connectedness may appear through flashbacks or flash-forwards, through external framing narrative, through linear or non-linear chronology or through direct cause-and-effect relationship.
Since J. B. has a Prologue and a play-within-a-play structure, it has an external frame for the internal play narrative. The frame has a cause-and-effect chronological progression while the inner play has its own cause-and-effect chronological progression. It is the external frame structure combined with the internal play-within-a-play structure that produce a sensation of episodes. Yet the cause-and-effect chronological nature of the entirety makes it clear that J. B. is climactic, with rising action preceding the climax and falling action following the climax.
But this is God in Job you're playing:
God the Maker: God Himself!
Remember what he says?--the hawk
Flies by His wisdom! and the goats--
Remember the goats? He challenges Job with them: (Prologue)