Complex sentence: Although he did not appear in Welles's second film, "The Magnificent Ambersons", in 1943 he joined fellow Mercury Theatre alumni Welles, Joseph Cotten, Agnes Moorehead, and Ruth Warwick in "Journey into Fear".
Split into simpler sentences: Although he did not appear in Welles's second film, "The Magnificent Ambersons". In 1943 he joined fellow Mercury Theatre alumni Welles, Joseph Cotten, Agnes Moorehead, and Ruth Warwick in "Journey into Fear".