How I Met Your Mother
"True Blood" star Anna Camp returns as Cassie in episode 8 of "How I Met Your Mother." CBS

Season 9 of “How I Met Your Mother” is supposed to be about Cristin Milioti’s character … yet viewers haven’t seen her in weeks! Fret not because Ted’s future wife is set to return in the Nov. 4 episode, “The Lighthouse.”

Episode 8 will find Robin’s fight with Barney’s mother, Loretta, escalating. And just like last time, Barney is stuck in the middle. Thanks to the promo video for “The Lighthouse,” we know that Robin won’t be backing down anytime soon. In fact, she might even be the one instigating the matter … by wearing Loretta’s beloved shirt that she won in the poker game.

While Barney struggles with his Robin/Loretta problem, Marshall will still be hiking to Farhampton for the wedding. According to TVGuide, Marshall and Daphne will take a pit stop at Ted’s mom’s house in Ohio. But a synopsis for “The Lighthouse” warns that the pair will end up “with a stowaway” on their road trip -- perhaps Ted’s step dad, Clint?

As for Ted? He’ll still be dealing with Cassie (guest star Anna Camp).

“How I Met Your Mother” fans will remember Cassie from episode 6, “Knight Vision.” Barney and Robin had put together a list of three prospects that Ted could secure for a weekend hookup. Ted had decided to jump on the first girl that approached him, Cassie -- which turned out to be a big mistake.

Offering to have “meaningless sex” with him, Ted ended up not getting lucky due to a series of events like:

-Cassie getting fired from her job over the phone and being told that everyone hates her.

-Cassie’s car with all her belongings in it being stolen.

-Cassie getting the flu.

-Cassie’s boyfriend Wesley breaking up with her -- and attending Barney and Robin’s wedding with another girl.

Ted may have managed to escape her in episode 7, “No Questions Asked,” but she’ll be back in episode 8 when the pair “try to enjoy a trip to the lighthouse.”

Meanwhile, TV Guide promises that Cristin Milioti’s “Mother” will be returning and that the “final minutes are not to be missed.” Why is that, you may ask? Because fans will see the two lovebirds together in a "significant flash-forward."

"How I Met Your Mother" season 9 episode 8 airs on CBS on Monday, Nov. 4, at 8 p.m.

Watch the promo video for episode 8, “The Lighthouse,” below. Let us know what you think will happen in the latest episode of “How I Met Your Mother.”