Lily Tomlin Brings Murderous Intrigue to 'NCIS'

Could McGee's own grandmother really be connected to a murder?
Emmy, Tony, and Grammy winner Lily Tomlin makes her debut on tonight's NCIS as Tim McGee's (Sean Murray) grandmother Penelope who may or may not be tied up in the killing of a naval officer who's death he is assigned to investigate.
Watch the clip for a preview of the all-new episode!
Don't miss NCIS tonight on CBS.