Robert Heinlein, Starship Troopers
Checklist, the Paul Verhoeven movie and the book:
The initial scenes are reasonable close to the original (Dubois, the crippled moral teacher, Mobile Infantry veteran, tries to instill civic virtue in his distracted pupils, elective course motivation). Doublet, the one armed, zero legged enlistment officer in the recruitment office. You cannot say that we did not warn you.
Rico experiences an existential crisis when confronted with the military brand of judicial punishment (ominously, the M.I. [Mobil Infantry] takes care of its own). Two unrelated breakdowns in disciplin occur: an unpremediated attack on a superior officer and a Linderberg case (ransom cum child molestation, the details remain somewhat hazy). Both are omitted out in the movie version (as best as I remember). The soul searching is instead caused by a lethal training accident (life ammo). There is agreement that Rico overcomes the crisis. Worth pointing out: the justification for the neck swinging (hanging) which follows the court martial in the book version is rather medieval (if not to say ontological). Approximately: the culprit either has no conscience (understood, is beyond the human pale) or his conscience was temporarily absent without leave. Guilty in either case. Rico, as a good Billy Bud, accepts the necessity for the punishment which he witnesses (once removed). In a manner of speaking: all the mortificationsof the flesh have a deeper purpose and are simply expressions of the prior's unending love for his wards. Less refined: spare the rod and spoil the child. In the same vein: it is not clear if M.I. recruits are actually issued fox cubs as pets to test their intestinal fortitude (the so-called eyebrow twitch test). If it worked for the Spartans. Denouement: Rico overcomes the crisis (aided by some timely Zen guidance from his erstwhile school mentor).
The novel subscribes to the folk believe that every recruit is just itching for a physical confrontation with his or her drill sergeant.
The feeding habits of the bugs are not specified in the original script. Movie version: brain slurping. Crass rather than class.
Rico's classmate Carl is earmarked for army intelligence (movie version). This is good for some classic confrontation. Upstairs planing versus expendable combat troops.
The punitive action on the planet of the 'skinnies' has been omitted in the movie version. This obviates the need to come up with a rational explanation for their initial alliance with the bugs. Somewhat construed in the first place.
The terror bombing (deep space meteor showering) of Buenos Aires serves as war catalyst in either version. It even reunites all surviving members of the Rico family (patches up a sweltering father-son conflict). Plausibility problem: If you can sling shoot meteors halfway across the known universe why bother with micro surgery. In cockchafer terms: do it right or do not do it at all.