Emily Wickersham is saying goodbye to! On Tuesday's season 18 finale, Wickersham's character, Ellie Bishop, left for a top secret undercover mission. Fans were surprised when Wickersham took to Instagram, confirming that the special agent is leaving the long-running procedural for good. «Hangin this hat and jacket up,» Wickersham captioned a series of photos, including one of her in an NCIS hat and jacket.