Question: what is the main idea of a tale of two cities

title: A Tale of Two Cities
text: John Barsad ( real name Solomon Pross ) : An informer in London and later employed by the Marquis St. Evrémonde . When introduced at Charles Darnay 's trial , he is giving damning evidence against the defendant but it becomes clear to the reader that he is an oily , untrustworthy character . Moving to Paris he takes service as a police spy in the Saint Antoine district , under the French monarchy . Following the Revolution , he becomes an agent for Revolutionary France ( at which point he must hide his British identity ) . Although a man of low character , his position as a spy allows him to arrange for Sydney Carton 's final heroic act ( after Carton blackmails him with revealing his duplicity ) . Roger Cly : Barsad 's collaborator in spying and giving questionable testimony . Following his chaotic funeral procession in Book the Second , Chapter 14 , his coffin is dug up by Jerry Cruncher and his fellow Resurrection Men . In Book the Third , Jerry Cruncher reveals that in fact the casket contained only rocks and that Cly was clearly still alive and no doubt carrying on his spying activities . Mr. Stryver : An ambitious barrister , senior partner to Sydney Carton . `` ... a man of little more than thirty , but looking twenty years older than he was , stout , loud , red , bluff , and free from any drawback of delicacy ... '' ; he wants to marry Lucie Manette because he believes that she is attractive enough . However , he is not truly in love with her and in fact treats her condescendingly . Jarvis Lorry gets him to see how unwise this course of action is and talks him out of it . ( Readers frequently misperceive that Stryver 's full name is `` C.J. Stryver '' , but this is very unlikely . The mistake comes from a line in Book the Second , Chapter 12 : `` After trying it , Stryver , C.J. , was satisfied that no plainer case could be . '' The initials C.J. almost certainly refer to a legal title , probably `` chief justice '' or `` circuit judge . '' ) Sydney Carton : A quick - minded but depressed English barrister , known as `` The Jackal '' in legal circles . When introduced , he is a hard - drinking cynic , having watched Stryver advance while never taking advantage of his own considerable gifts : Dickens writes that the sun rose `` upon no sadder sight than the man of good abilities and good emotions , incapable of their directed exercise , incapable of his own help and his own happiness , sensible to the blight on him , and resigning himself to let it eat him away . '' In love with Lucie Manette , she cares about him but more as a concerned mother figure than a potential mate . He ultimately becomes a selfless hero , redeeming everything by sacrificing his life for a worthy cause .