Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_74227 ( "Series no." real, "Season no." real, "Title" text, "Directed by" text, "Written by" text, "Original air date" text, "Production code" real, "U.S. viewers (millions)" text )

### Question ###
at most what number in the series was the episode 'chet episode'?

### Accurate SQL ###

SELECT MAX("Series no.") FROM table_74227 WHERE "Title" = 'Chet Episode'