Horror nerds that we are, Fun Size Horror would love to share with you some of our favorite genre films, but with a twist: instead of just listing off some favorites, each week we'll offer up a pairing of two horror films that complement one another in unique or fascinating ways: Double Feature Friday.

Today's entry features two very different intricately-crafted and suffocatingly-paranoid horror-thrillers that both have very similar concerns--how adults deal with grief and trauma, and how the choices that mark their attempts at recovery can invite madness. Also? Both films are batshit insane.

POSSESSION (1981/ 124 minutes/ dir. Andrzej Zulawski)

Possession is a film that defies categorization or description--it simply must be experienced to be understood. That said, the broad strokes: a Cold War-era spy comes home to find his wife has recently miscarried, is engaging in an affair, and may be losing her mind. 

What spirals out of that discovery--doppelgangers, mass murder, Lovecraftian monsters, possibly the apocalypse, and what has to be the most epic seizure in cinema history--all serve as mind-bending literalizations of the brutal emotional horrors suffered after the loss of a child, the hell of betrayal, or a disintegrating union. The film is harrowing journey into the tunnel of madness that follows loss, and its resolution of that madness is no less horrifying.  

THE INVITATION (2015/ 99 minutes/ dir. Karyn Kusama)

While The Invitation is a far easier film to summarize that Possession, it's twisty-turny series of plot-kinks, narrative left-turns, and shocking surprises makes any detailed description simply a series of spoilers that rob the film of its power (and boy oh boy, is it powerful).

Here's what you need to a know: two years after the death of their child, a man's ex-wife invites him, his new girlfriend, and a group of mutual friends to her house for a dinner party that evolves into conversation about the myriad of ways to (and to not) confront grief after the death of a loved one. Then it evolves into... something else. Suspicions are raised, paranoia becomes nearly The Thing-level suffocating, and madness erupts... with a final scene that actually manages to rival The Possession's in terms of the insanity of its implications.