'How I Met Your Mother' Season 9 Spoilers: Anna Camp Posts Instagram Photo of 'HIMYM' Set, Receives 100,000 Followers; ‘True Blood’ Actress Will Appear In 1 Episode

"How I Met Your Mother" season 9 spoilers! Anna Camp, who is known for her character on "True Blood," will join "HIMYM" in its final season for 1 episode. Anna Camp posted an Instagram photo on her Twitter account of the "How I Met Your Mother" set a few days ago.

Anna Camp achieved 100,000 followers on her Instagram account today.

The 30-year-old actress will portray the character Cassie on "How I Met Your Mother." Cassie is a guest at Barney and Robin's wedding, and some spoilers suggest that she will catch Ted Mosby's eye first before he ends up with 'The Mother,' IB Times reports.

The character Cassie is described as "one of the most attractive and available" guests in the wedding.

"Working it out on the set #HIMYM #finalseason!" Anna Camp excitedly captioned her Instagram picture, which she also shared on her Twitter account @TheRealAnnaCamp.

The photo was of the "How I Met Your Mother" set with two directors chairs with lights and a scene set up in the background.

According to IB Times, Camp's character has been signed on for one episode where she is believed to have a "brief dating encounter" with Ted.

Season 9 of "How I Met Your Mother' will begin with an hour-long premiere with episodes called "The Locket" and "Coming Back," as the group heads to Long Island to attend Barney and Robin's wedding, IB Times reports.

"How I Met Your Mother" Season 9 returns on Monday, September 23, with the special back-to-back episodes starting at 8pm on the CBS.