Jack Palance received his first Oscar nomination for portraying Lester Blaine in Sudden Fear.
Lester Blaine first crosses paths with Myra when she refuses to cast him in her play because he lacks stage presence. Anyways he meets her later, and charms her off her feet basically. This is quite a challenge that Palance must fulfill to make this romance believable. Palance though is actually charming enough in these early scenes to make this aspect of the film believable. He is not charming in say a Clark Gable sense, or more appropriately a Robert Montgomery in Night Must Fall sense, but really an average Joe charm that works well.
Palance is also quite commanding in the beginning of the film. His control he takes over Crawford is made quite believable by both actors. This command is necessary to make the actions of Crawford's character believable suggesting as giving him a great place in her will. I will say Palance does make his control over her properly realistic. I almost felt he was the male lead because of the first half of the film. In the second half of the film though his role does become limiting quite considerably, when the film does almost completely focus on Joan Crawford's character.
Palance though suggests that underneath his charm there is a selfish motive underneath all what he is doing. It turns out that he actually only romanced and married Myra to get her fortune. He intends to, along with his ex-girlfriend Irene Neves. I think Palance did a fairly good job at the beginning of the film hiding Lester's true attentions, but nonetheless subtlety suggesting them at the same time. His revelation is well handled, his whole facade is very believable, and I think he did not make his evil intentions completely obvious at the beginning of the film making it more effective when he did.
Palance at the end of the film is properly chilling when he finally undergoes his plan of action. I liked it that he did not turn Lester into a complete psychopath precisely, but clearly a man who is a bit nervous himself. I liked at the end that he really goes over the edge, and becomes incredibly nervous and frantic at the end in his attempt to fulfill his plan and not get caught. Overall a strong effective performance from Jack Palance.