Complex sentence: Her appearance in play caught the attention of Warner Bros.' president, Jack Warner, who signed her to a long-term contract and cast her in Warner Bros film adaptation of "Life Begins" later that year.
Split into simpler sentences: Her appearance in play caught the attention of Warner Bros.'president, Jack Warner, who signed her to a long-term contract with the studio. And cast her to re-create the role in Warner Bros' film adaptation of "Life Begins" later that year.