This, the fifth novel in the Palliser series, is according to David Skilton in his introduction `the key work in the (...) series'. Now I wouldn't know about that, not having read the sixth and last novel, but what I do know without a shadow of a doubt is that this is a very very good novel in its own right.
Trollope loosely intertwines two plots in `The Prime Minister'. In the `political' plot Plantagenet Palliser is asked and eventually (though reluctantly) accepts to become prime minister, to the great pride and joy of his wife Lady Glencora. In the `social' plot, Emily Wharton, daughter of a wealthy lawyer, falls in love with and marries, against the advice of all her friends and relatives, a certain Ferdinand Lopez (about whom nobody seems to know much, not who his parents were, or how he makes a living). In both cases the protagonists come to realize before long that it's not all gold that glitters: Palliser learns that being prime minister is not all it's made out to be, and Emily discovers how deceptive appearances can be when she gets to know her husband better.
Trollope investigates several themes in `The Prime Minister' by (implicitly) comparing and contrasting the main characters. As to the men: Plantagenet Palliser is indeed `the perfect gentleman' but this has its drawbacks too, or so it seems: he is scrupulous to a t, unable to socialize and `joke around' with other men, and ever in doubt of his own capability to be a good prime minister. The question Trollope raises is ultimately: can a true gentleman be a good prime minister? Ferdinand Lopez on the other hand is the opposite: he has all the outer trappings of a gentleman, but it turns out that beneath this thin veneer he is a ruthless and egotistical opportunist. However, Lopez has an energy and `can do' mentality, a will to succeed, that Palliser lacks.
The two main female characters too are contrasted: Lady Glencora has been married for years now and, in spite of his shortcomings, truly loves her husband. She tries to support him in all his efforts but in doing so `puts her foot in it' and causes him severe embarassment. Emily Wharton on the other hand tries to love and obey her husband as she feels she should, but finds this increasingly difficult when she discovers he sees her father as nothing but a milch cow (with her as the dairy maid).
Although there is a happy end of sorts, the overall effect of the novel is clearly rather gloomy and depressing, but I hasten to add that this for me by no means detracted from the joy of reading it. It's the eleventh Trollope-novel in a row I've read now, and to me one of the very best so far! And so, with a mixture of both anticipation and regret, it's on to the sixth and final part in the Palliser series, `The Duke's Children'!