Complex sentence: Later, Skyler (Anna Gunn) receives a phone call from Marie (Betsy Brandt), who informs her Walt is back in town, unaware that Walt is already with Skyler.
Split into simpler sentences: Later, Skyler (Anna Gunn) receives a phone call from Marie (Betsy Brandt), who informs her Walt is back in town. Marie is unaware that Walt is already with Skyler.