The team searches for a serial killer who is preying on married couples; Hotchner looks to a team member to fill JJ's vacant role.
After Hal and Lois leave town for a getaway, "squatters" crash Reese's party, take over the house and refuse to leave.
When Louis and Jessica are pressured into volunteering due to budget cuts at school, the kids see a new side of their parents.
A monster starving for human brain matter tries to remedy his own unusual eating habits.
Jules and Ellie differ on whether it's more difficult to raise a baby in your 40s than in your 20s. Ellie tricks Jules into watching Baby Stan on her own for a day, but Jules is determined to prove how easy it is.