'The Big C': Cathy Quits Chemo in First Look at 'Hereafter' (Exclusive Video)

The end is near for Showtime's The Big C.

The premium cable network will debut the first promo for the final season of its Laura Linney dramedy on Sunday, but The Hollywood Reporter has the first look at the trailer for Hereafter.

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In the clip, Linney's Cathy Jamison receives some life-altering news and makes a game-changing decision: her tumors are not just back but are growing and she's on the verge of ending her chemotherapy treatments.

While some things are ending -- namely Cathy's teaching career -- it appears that her troubled marriage to Paul could be headed in a new and greatly improved direction, as the duo shares a sweet kiss during the clip, which also takes a look back at some of the key moments from the first three seasons (RIP, Marlene).

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"I feel good about how we finish the story, all of us together," Linney told reporters in January during the Television Critics Association's winter press tour. "The lesson I learned over and over again is … that nothing is ever as you think it's going to be … It unfolds in unexpected ways, always."

Check out the exclusive clip, above, and hit the comments with your thoughts on how the final season should end. The final season of The Big C  --  which consists of four hour-long episodes -- returns Monday, April 29 at 10 p.m. on Showtime.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit