Complex sentence: The explosion is witnessed by Jim Hill (McClure) and his wife Carol, who begin to wonder what is going on here, especially when Carol's dog goes missing during the following night and the two find its dismembered corpse on the nearby beach.
Split into simpler sentences: The explosion is witnessed by Jim Hill (McClure) and his wife Carol. Later, Carol's dog goes missing and the two find its dismembered corpse on the nearby beach.