Complex sentence: Billy somehow escaped, but we haven't seen Boogie since until he returned in the TV movie "Billy & Mandy's Big Boogey Adventure", and his ship from the game made an appearance.
Split into simpler sentences: Billy somehow escaped, but we haven't seen Boogie since. Boogie returned in the TV movie "Billy & Mandy's Big Boogey Adventure", and his ship from the game made an appearance.