Max calls an all-staff meeting after discovering one of his employees is leaking secrets to their biggest competitor, Knightsbury Lane, owned by the company's former boss, Andrew Sumner. Max had plans to roll out an amazingly whimsical cow-inspired line of slippers in the coming weeks, but the competitor has beaten him to the punch! Because of this, Max orders Sean to find the mole among them and fire that person. If he doesn't, Max will replace the entire staff with robots and runaways. As Max leaves, Liz tells Sean she might be the mole he's seeking!
Sean knows how Liz can be at weddings; she drinks too much and starts blabbering to any semi-attractive male within a 30-foot radius. Recently, Liz ran into Andrew at a wedding and the two shared a few drinks. She didn't divulge any secrets, but she did record a Vine with her former boss, and it's going viral! Liz worries Max will see the Vine and erroneously connect the dots. Sean tells her to calm down, since he's on the case to uncover the true perpetrator. This doesn't help Liz at all, though, since she thinks Sean is a lousy detective... after all, it took him 26 years to discover he was gay!
When Sean gets home, Lorna is waiting for him with "apocalyptic" news. Ellie has a new friend, Becky, and in Lorna's estimation, she's a "jazzy little mattress jockey." Since Becky is a senior and has an older boyfriend, Lorna thinks the entire situation is headed for disaster. If Ellie starts taking after her older friend, maybe she'll get to thinking she can get whatever she wants if she just performs "favors" for impressionable young men. Obviously Sean doesn't want any of that. Sean promises his mother that he'll do something about the Becky situation.
At work, Sean visits with each member of the staff, but the only things he uncovers are uncomfortable personal secrets about his underlings: Jerry reveals he's socially incompetent - hardly breaking news, and Mrs. Ling says she just straight up hates Sean. Hunter fears Sean's planning on framing the "black guy." Max enters the offices with a manila folder bursting with information on every employee. It seems he's hired a private investigator and reports have been compiled on everyone in the office. Max reveals that Sean used the company credit card to stay at the Drake Hotel with another person. When Liz and Hunter find out that "other person" was Andrew, i.e. Sean had a one-night stand with him, the entire office assumes Sean slept with his boss to get ahead in the company.
When Sean gets home, Lorna says "the whore is in the house," which he assumes to be a personal attack until he realizes his mom is talking about young Becky again. Becky's driving around in a hot new convertible, which Lorna can only assume was a gift in exchange for God knows what. Lorna tells Sean it's only a matter of time before Ellie pulls up in a convertible of her own. Sean pulls Ellie aside and tries to warn her about Becky, but given his situation with Andrew - and the ambiguity as to whether he's used sex to get ahead in life - Sean ultimately can't bring himself to reprimand his daughter. Lorna looks on with disgust at yet another failed parenting opportunity. When Ellie leaves, Sean tells Lorna about Andrew, and she is shocked he didn't hold on to that guy... they could've been millionaires!
Confused about what happened between him and his boss that fateful night, Sean pays Andrew a visit in hopes of discovering the truth, but Andrew's not interested in rehashing the past and instead openly begs for Sean's affection. Although it feels like pulling teeth, Sean eventually gets Andrew to admit his promotion was completely self-earned and unrelated to their "amazing night at the Drake." As Andrew continues trying to win Sean's affection, Sean realizes where his convictions lie; he cannot be bought, no matter what anyone says. When Sean hugs Andrew goodbye, he finally realizes who the mole is...
The next day at work, Sean reveals his discovery. When he hugged Andrew goodbye, Sean smelled the distinct aroma of Max's conditioner. After a series of investigations, Sean came to the conclusion that Andrew and Max have the same hairstylist, and Andrew has been paying that person for secrets Max blabs about during haircuts. Embarrassed, Max pouts away to his office, and Liz thanks Sean for saving her job!
Sean plays detective when company secrets are leaked to their biggest competitor; Craig Ferguson guest stars.