I happen to like Leslie Howard, in his better films. Yet, for some reason, his performance in OF HUMAN BONDAGE never has moved me tremendously. I first saw the film on my college campus in 1972 and the reviewer in the college newspaper made the comment that in the 1930s and 1940s Howard played the roles supposedly later picked up by Dirk Bogard as the man who was born to be betrayed. This is not usually the case (off hand I think of Ashley Wilkes as a man who might be betrayed, if he and Scarlett O'Hara were meant to be an item by Margaret Mitchell - but Ashley loved Melonie, not Scarlett). Howard could play any type, and a role like R. J. Mitchell or Professor Henry Higgins is not one who is betrayed.*
(*One can make the case that Philip Armstrong Scott is betrayed by the two strangers he shows hospitality to in 49TH PARALLEL, but they are Nazis who consider him - a liberal, westerner, Canadian - fair game to double cross in wartime. It isn't the same as emotional betrayal, and Howard does not shrivel up as a result, but faces the Nazis and captures one after beating him up.)
I think what the reviewer meant was that Howard could be soulful - or try to be soulful. Witness his poet - dreamer - wanderer in THE PETRIFIED FORREST. But that character was not betrayed, except by history perhaps (as he feels his type is as out of date as the gangster played by Humphrey Bogart). The character of Philip Carey in Somerset Maugham's OF HUMAN BONDAGE is soulful too. He is sensitive for several reasons. He has an interest in art and tries to become a painter - but unlike the artist Strickland in THE MOON AND SIXPENCE he has no real talent. So he decides to concentrate on medical studies, accentuated by a club foot condition he has. Here he is a man with low self-esteem who is set up to be betrayed.
Philip finds that betrayal in the form of Mildred a Cockney waitress (Bette Davis) who is mercenary and as selfish as they come. Why Philip falls for her is not really addressed in the film, but he does find the woman fascinating. And she finds him an easy meal ticket. Ironically in being so captivated by this slut, Philip fails to notice two other women who are interested in him (Kay Johnson and Frances Dee), and are more fit to be his mate. He also keeps finding himself forgiving Davis when she has affairs with other men (Alan Hale and Reginald Denny - the latter a friend of Howard's).
Although Howard's performance captures the doormat tendency of Philip towards Mildred, he really does not show enough passion (until late in the movie, when he turns on her). That is why I find I never cared for his performance here - it lacks any reality. His later tortured insistence in GONE WITH THE WIND that he loves Olivia De Haviland, not Vivian Leigh, has more consistency with a man in love. But the performance of Davis as Mildred makes the film important. She had a wide variety of parts up to 1934, like the girlfriend of the deaf pianist in THE MAN WHO PLAYED GOD or the spoiled heiress who gets murdered in FOG OVER FRISCO or the mouse-like secretary in THREE ON A MATCH. As Mildred she finally showed she could be a major actress by playing a selfish bitch.
Curiously her performance was not all of one note. While she uses and abuses Howard for two thirds of the film, culminating in that famous scene where she shows how disgusted his kissing of her made her, her last scenes show she too could fall apart due to her health deteriorating, and her inability to keep any honest jobs. When Howard rejects her the viewers fail to note how equally vicious he becomes (he asks what happened to her baby - she tells him the baby died and Howard says brusquely that he is glad, which is hardly the response she expects). In the end Howard does finally get his life in order, but Mildred ends a casualty (ironically her death discovered by her old boyfriend Denny on a medical call). The Motion Picture Academy of Arts and Sciences did fail to nominate Davis in 1934 (leading to the largest write - in campaign in it's history, and a permanent change in it's rules), but Davis was established as a star. In one year she won the Oscar as Joyce Heth in DANGEROUS. And in two years she co-starred with Howard again (as equal stars) in THE PETRIFIED FORREST.