It is the romance of Antonius Diogenes that holds Doerr's novel together: that's what Anna translates and saves and what Zeno translates (and--spoiler alert--Constance's grandfather was one of the 5th graders performing Zeno's play, so her future is not too distant). Aristophanes is not really present in Doerr's work, only in the fragments of Antonius Diogenes that Doerr invents. I would beg to differ: the novel holds together quite well and is a lovely and moving read.