Harington and Leslie are set to tie the knot at her family's castle in Scotland on Saturday.
The couple, who met as onscreen lovers on 'Game of Thrones,' have been engaged since September.
ET exclusively debuts a first look from Sunday's episode of the original CBS All Access series.
The original series, a spinoff of 'The Good Wife,' debuts new episodes Sundays on CBS All Access.
She literally kicked him out of the house.
The co-stars got engaged last month.
The 30-year-old actress flaunted her ring while out and about in London, England, over the weekend.
