Girl with Green Eyes seems typical of the period of British "Kitchen-Sink" drama films (I saw it as the 2nd part of a double bill with The Leather Boys and the theme being Rita Tushingham performances, though this is dialed down a little from that turn), and that's what's good but not terribly memorable about it all. It's realistic in some of the basic character interactions, though it has a bouncier/more emotionally-cued up score than the material should have, if that makes sense. It seems like a minor point but Desmond Davis clearly wanted to get a lot of emotional/romantic/tragic pull out of the music by John Addison, and it may have been too much for this lot of realism (how typical this is by the way, it's produced by Tony Richardson).
The story is actually an Irish-Kitchen-Sink movie, though with a couple of British touches: a young girl in Dublin, who originally was from a fairly lower-class farm that was highly religious but working *very* Irish class all the same, is working at a bookstore and finds that there's an author that she would like to meet along with her friend/roommate Baba. Peter Finch is this man, and soon Kate, the girl of the title, takes a real liking to him, and after not too long he to her. So they "hook up", so to speak, and this brings on problems, both external in force (he's technically married with a kid in another country, she's got pressure from her family not to have anything to do with this "Godless heathen), and more about the fact that it's a man who could be old enough, if only barely, to be her father.
This is a story explored in many kind of films, whether it's throw-a-dart-and-hit a Philip Roth story, or of course Manhattan. There's enough chemistry and charm between the two leading people as Tishingham, even dialed down, is delightful, and Finch does a lot playing usually-crusty and mostly sardonic/sarcastic speaking (if there had been a remake some years back I could've seen Alan Rickman in his role), plus Lynn Redgrave being wonderful and funny in her supporting place. But there's not much here that elevates it past its time and place; it's a perfectly fine drama, and it doesn't distinguish itself past some insights, which are only insightful up to a point, that you may need to grow as a person (or can never meet the other on the flipside due to losing "youthful vigor" as an aging man) to have a relationship work sometimes.
There's a nice, tender feeling to the film, Finch and Tushingham make a good pair on screen (precisely because we kind of know, deep down, it's not only not going to work but it can't not ever work, if that makes sense, so let's see them in the little moments) and that should work for anyone looking for that. Although some things that contribute to the 'hasnt-aged-terribly-well' is, say, when the film is edited so early on in their courtship Eugene and Kate talk and one part of a sentence begins in a new location and then another and another, and it feels distracting.
