-- Database schema
| Episode : episode_id [ TEXT ] primary_key , series [ TEXT ] , season [ INTEGER ] , episode [ INTEGER ] , number_in_series [ INTEGER ] , title [ TEXT ] , summary [ TEXT ] , air_date [ DATE ] , episode_image [ TEXT ] , rating [ REAL ] , votes [ INTEGER ] | Keyword : episode_id [ TEXT ] Keyword.episode_id = Episode.episode_id , keyword [ TEXT ] | Person : person_id [ TEXT ] primary_key , name [ TEXT ] , birthdate [ DATE ] , birth_name [ TEXT ] , birth_place [ TEXT ] , birth_region [ TEXT ] , birth_country [ TEXT ] , height_meters [ REAL ] , nickname [ TEXT ] | Award : award_id [ INTEGER ] primary_key , organization [ TEXT ] , year [ INTEGER ] , award_category [ TEXT ] , award [ TEXT ] , series [ TEXT ] , episode_id [ TEXT ] Award.episode_id = Episode.episode_id , person_id [ TEXT ] Award.person_id = Person.person_id , role [ TEXT ] , result [ TEXT ] | Credit : episode_id [ TEXT ] Credit.episode_id = Episode.episode_id , person_id [ TEXT ] Credit.person_id = Person.person_id , category [ TEXT ] , role [ TEXT ] , credited [ TEXT ] | Vote : episode_id [ TEXT ] Vote.episode_id = Episode.episode_id , stars [ INTEGER ] , votes [ INTEGER ] , percent [ REAL ] |
-- -- What is the title of the episode that has the highest number of crews in the Art Department?

SELECT T2.title FROM Credit AS T1 INNER JOIN Episode AS T2 ON T1.episode_id = T2.episode_id WHERE T1.category = 'Art Department' GROUP BY T2.episode_id ORDER BY COUNT(T1.category) DESC LIMIT 1;