SELECT MAX("No. in season") FROM table_64453 WHERE "Written by" = 'chris hawkshaw'
Which episode was the last written by chris hawkshaw this season?
CREATE TABLE table_64453 (
    "No. in series" real,
    "No. in season" real,
    "Title" text,
    "Directed by" text,
    "Written by" text,
    "Original air date" text
)