The Millie/Tim hybrid is played by Alison Brie, but you can be forgiven if you don’t recognize her at all. In addition to extensive makeup work on set that saw parts of Dave Franco’s visage applied to the actresses, there were also visual effects employed that changed the shape of her face to be more like her co-star’s/husband’s. Shanks explained,

Alison Brie stars as Millie, a teacher who's ready to take the next step in her relationship: marriage. Her partner of more than a decade, Tim, played by Dave Franco, is an aspiring musician too paralyzed by his emotional baggage to commit.

Spoilers! Married "Together" movie stars Alison Brie and Dave Franco unpack that gruesome and strange final scene in their new horror rom-com.