The Go-Between is a collaboration between director Joseph Losey and writer Harold Pinter, based on the novel by L.P. Hartley. It tells about ageing Leo remembering his summer days in his school friend's place. This friend's family belongs to the upper class, but they receive young Leo kindly. Marcus's (Marcus is Leo's friend) older sister, beautiful Marian, takes Leo to the town and buys him a suitable summer suit and since then Leo likes her very much and will do anything for her. Marian takes this opportunity to use Leo as a go-between, to bring her messages to her lover, farmer Ted Burgess, whom she can never marry. It ends badly when Marian's mother finds out about this affair.
Marian seems to depend on Leo so much that she becomes angry when Leo finally says he cannot give her message to Ted Burgess anymore because Leo is afraid Hugh (Marian's fiancé) will be hurt. Leo is fond of Hugh as well. Marian is so angry that she says to Leo rude things.
The differences between upper class and workers are described well in this movie. However I find it hard to believe that young Leo is really that innocent. The story is set in 1900 and probably at that time 13 year-old boys were really that ignorant. It's quite annoying to see he didn't see right away the significance of the messages between two lovers he brought. And it's very annoying to see the scene where he annoyed Ted Burgess with his questions about men and women. Another annoying thing is Julie Christie's hair, which was too much.