Ever since the news first broke that 'How I Met Your Mother' would return for a ninth and final season, fans have been anxious to see the long-teased wedding between Robin and Barney play out, in which the show's title supposedly lives up to its name. Before that day this spring however, Barney and Robin will have a number of decision to make about "The Fortress," so what about the latest clip from Monday's episode seems darker than the show usually operates?

Barney Stinson will have a major decision to make when Monday sees the first all-new 'How I Met Your Mother' episode of March, the aptly-titled "The Fortress." As the wedding day for Barney and Robin approaches, the two will have to come up with a compromise with regard to their living situation, given that Robin is none-too-eager to live in such an admitted bachelor pad, while Barney similarly hesitates to give it up.

CBS has released a new clip from Monday's episode that ventures in to some rather heavy territory, first teasing the adoption issue between the pair before showing a rather dark fate for girls Barney doesn't wish to stay in his apartment. Surely season 9 wouldn't turn Barney into a serial killer, right? Right?

Take a look at the latest clip from How I Met Your Mother's March 18 episode "The Fortress" below, and give us your predictions for the remainder of the season in the comments!

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