Bruce Baxter is a famous and successful actor who was to star Carl Denham's film.
He originally took part in the rescue group for Ann Darrow and, during the running of the Brontosaurus, brings the great reversal of these dinosaurs, as he had a shot one of the Brontosaurus in the legs, causing it to trip, obstructing the others' paths and causing them to fall over one another. After abandoning the search for Ann (justifying it by declaring "I'm an actor with a gun. And I've lost my motivation"), he made his way back to the Venture.
Later he had a change of heart and returned to save Jimmy, Carl and Jack Driscoll from the insects after they had fallen off the log. Captain Englehorn gives him credit for this, as he "insisted on a rescue mission" - in contrast with his previously cowardly nature. Carl Denham also gives him credit for rescuing Ann after they return to New York; a blatant lie as it was Jack who had done so. However, Bruce goes along with it.
However, while reciting, Bruce realizes that Kong can break free from his chains. He tries to escape but he is slowed by photographers. Bruce perhaps died, as he was maybe unable to escape before Kong broke loose, but there is not sufficient information to accurately determine this. Most of the audience made it out alive, so it seems likely that he did too, given his tenacity and seeming ability to survive frequent dangers.