“The human soul enjoys these rare, classic periods, but, apart from them, we are seldom single or unique; we keep company in this world with a hoard of abstractions and reflections and counterfeits of ourselves—the sensual man, the economic man, the man of reason, the beast . . . indistinguishable from ourselves to the outward eye . . . knowing we have a secret we shall never share.” 
In 1942, Charles Ryder is a middle-aged captain in the British Army during World War II stationed in the Scottish countryside. He organizes his troops to move them to another location by train overnight. At the first light he finds himself unexpectedly billeted at Brideshead, a mansion whose owners he once knew. Told in retrospection, the story begins in 1923, in Oxford University, where Charles becomes friends with Sebastian Flyte, the younger son of an aristocratic family, who is the “most conspicuous man of his year by reason of his arresting beauty, and eccentricities of behavior.” The friendship quickly grows to be a bondage that bears an ambiguously homosexual undertone when Charles is called back to the palatial Brideshead after Sebastian incurs a minor injury during summer. At the time Charles also meets Julia, the standoffish sister who plays an intermittent and enigmatic part in Sebastian’s drama. Through Charles’s recollection of a harsh and acquisitive world that Brideshead is, Waugh, in favor of an emphasis on male friendship, writes that Charles has been in search of love and that he has no mind then for anything except Sebastian.
. . . at last, I should find that low door in the wall, which others, I knew, had found before me, which opened on an enclosed and enchanted garden, which was somewhere, not overlooked by any window, in the heart of the grey city. 
The metaphor comes to inform Brideshead Revisited on a number of levels. But quickly Charles realizes that Sebastian’s family is overwrought by Catholicism. As his intimacy with the Marchmains grows he also becomes part of the world Sebastian seeks to escape because he has become wary of family and religion. His life is a struggle between what he wants to do and what he believes his church requires him to do. He descends into alcoholism, which the Marchmains denies, for solace. Charles constantly questions members of the Flyte family about their beliefs and even makes light of religion. “Is it all nonsense? I wish it were true.”
Julia Flyte is wayward and obscure. Only toward the end of the novel, after she has begun an affair with Charles and divorces her husband, does she thinks about being a Catholic. She expresses concerns that her behavior has filled her with sin that her mother, who is adamantly Catholic, has born to her grave. Even though she loves Charles, I am not convinced that Charles reciprocates the same kind of love. He is only emotionally in love with Julia because he sees Sebastian in Julia, and that his wife has been unfaithful. For nearly a decade since he sees the last of Brideshead until he reunites with Julia on a ship, Charles bears along a road outwardly full of change and incident (he becomes an architecture painter and gets married to a woman whose words render his bowels shrivel), but never during that time, except sometimes in his painting, does he come alive as he had been during the time of his (platonic) friendship with Sebastian. He indicates to Julia that Sebastian was the “forerunner,” the first person in the Flyte family with whom he fell in love.
I have not forgotten Sebastian. He was with me daily in Julia; or rather it was Julia I had known in him, in those distant, Arcadian days . . . every stone of the house had a memory of him, and when I heard him spoken of by Cordelia as someone she had seen a month ago, my lost friend filled my thoughts. 
Throughout the novel, Charles Ryder believes that what was is preferable to what is. His platonic relationship Sebastian might have prepared him for his maturing and his later conventional, romantic enterprises with Lady Celia and Julia, but he has lived the time of his life with Sebastian.
If it could only be like this always — always summer, always alone, the fruit always ripe. 
He is obviously a man who values the past, which is largely made up of memories of Sebastian. His time with him makes up of the Arcadian days, which is part of the title of Book One. Arcadia refers to a pastoral and mountainous region of ancient Greece used extensively in painting and literature to denote a sort of Utopia or a place where life is wonderful.
Brideshead Revisited explores friendship, religion, and reminiscences in life. Book One, which emphasizes on the relationship between Charles and Sebastian, is more poetic and lyrical than the second half, which doesn’t take place until a decade later. Waugh, or rather through Charles, portrays a family divided by an uncertain investment in Roman Catholicism and by their confusion over where the elite fit in the modern world.
351 pp. [Read/Skim/Toss]