Complex sentence: Alastair (Mark Rolston) makes his debut in the episode "I Know What You Did Last Summer", in which he seeks to capture and interrogate Anna Milton, a fallen angel who can still hear the conversations of other angels.
Split into simpler sentences: Alastair (Mark Rolston) debuts on-screen in the episode "I Know What You Did Last Summer". He seeks to capture Anna Milton, a fallen angel who can hear the conversations of other angels.