For factual timelines and a deeper sense of reality, die-hard Def Leppard fans should view VH1's "Behind the Music" documentary about the band rather than this dramatization, in which the real bandmembers had no real input other than contributing their songs. That being said, "Hysteria: The Def Leppard Story" has some interesting points.
This made-for-TV film does manage to convey the hardships and triumphs of Def Leppard in a thought-provoking manner, surmounting the somewhat-less-than-accurate script with fine performances by comparatively unknown (at least in the U.S.) actors. Unfortunately, due to the many artistic liberties that were taken (in order to condense the story to a manageable viewing time and to make the content acceptable for television audiences), quite a bit of crucial information was omitted, and many of the characters received short shrift as well.
The actors' abilities to make something substantial from the two-dimensional parts they were thrust into, let alone using their performances to push this film past mediocrity, is astounding. The most blatant example of this is in Adam MacDonald's portrayal of bass player Rick Savage. MacDonald breathes as much life as possible into the character, but it's plain to see the writers had no interest in its development, evidently because the fact that Savage was one of the founding members of the band -- even before lead singer Joe Elliott --was not as screenworthy as Steve Clark's fear of his father, or Rick Allen's reckless driving. This strikes me as an insult to the real Savage as well as to MacDonald, but more importantly, it suggests that there is probably a great deal more to this story than we are allowed to witness. Whether this is by choice of the bandmembers or the producers is unknown, but the overall feel is that of Cliff's Notes -- we have enough information to pass the quiz, but no more.
See this film as a supplement to, not as a substitute for, "Behind the Music".