Complex sentence: She returned for a third time in the episode "Safe Harbor", which had a plot that illustrated the role of the CGIS in supporting the Department of Homeland Security (DHS) through maritime law enforcement and counter-terrorism missions worldwide.
Split into simpler sentences: She returned for a third time in the episode "Safe Harbor". The story illustrates CGIS in supporting Department of Homeland Security (DHS) maritime law enforcement and counter-terrorism missions worldwide.