Complex sentence: She causes him to have an angina attack and saves his life, but when Darren refuses to help her, Sienna begins to scheme against Nancy when she discovers she slept with Rick Spencer (Victor Gardener).
Split into simpler sentences: She causes him to have an angina attack and saves his life. But when Darren refuses to help she begins to scheme against Nancy when she discovers she slept with Rick Spencer (Victor Gardener).