Elliot and Olivia were questioning Lindsey Royce as a possible suspect for her husband's murdered mistress. Lindsey was telling the Detectives about her fustrations of being a housewife and mother, she likes to go out some nights to enjoy herself.
Lindsey: I bet you're married. Did it ever cross your mind that your wife might wanna do a little more than just make beds and cook dinner?
Later, Elliot and Olivia returned to the Royces' home with more questions. Instead they found Lindsey and her 3 children shot dead and her husband, Malcolm, was also shot but still alive. He found out about the deaths of his family at the hospital. Elliot was shaken up, leaving Olivia to update Don
Kathy: Did it help?
Elliot: Look, I called. She said it was okay
Kathleen: That's not what I mean. We're your family, not some booty call. Come home or don't. But there's nothing in between.
Before Elliot could answer, his cell rang and Kathleen went back up
Elliot was interrogating Malcolm for a confession of killing his family and mistress in fear of losing everybody he loves.
Elliot: Look, I've been married over 20 years, I know how good it was in the beginning. And then the kids came...and the sex dried up. And you wind up talking about bills and braces and college tuition. And all you want is the damn romance back. And then you meet another woman who makes you feel so alive
Elliot continues on
Note: Elliot and Kathy conceived their fifth child, Eli, in this episode. Elliot did not check on Maureen- she must have moved out?