Cal wanders through the office of social network app Seekout, taking pictures with his smartphone. Then he confronts Zach Morstein about firing one of his co-founders, Kyle Putnam, just before the company went public and made billions. Zach figures that the company's third co-founder, Claire, must've hired Cal, adding that he and Claire are longtime friends. So tell her she's safe, Zach says with a smirk.
When Cal and Gillian meet Claire at the Lightman Group office, Cal's concerned about Zach's smirk and fears that Claire will suffer the same fate as Kyle. Claire admits that Zach has changed, but she says that they're still friends and she doesn't want to fight him. When Cal wonders if the change is more personal than business-oriented, Claire clams up and leaves.
While Gillian - who was Claire's former therapist - vows to protect her, Eli observes that Claire quickly took Zach's side. Gillian claims that Claire is simply conflicted because friendship means everything to her.
Meanwhile, a young man enters Cal's empty office, sees a $100 bill on the desk, and walks away. Cal - who's been watching - stops him. He's Marquis "Key" Turner, and Ria wants Cal to give him a job. Cal wants someone followed and gives Key the $100 for expenses.
Cal comes home to a moaning Emily, who's getting her hamstrings stretched by Liam; just then Gillian calls. Cal races away and finds Gillian in tears because she went to check on Claire, found she'd been stabbed, and couldn't save her.
Detective Wallowski tells Cal and Gillian that the Seekout app on Claire's phone placed Kyle in Claire's apartment at the time of her murder. Cal says that Kyle is not the killer. Wallowski adds that the cellphone tower records corroborate Kyle's presence and those records can't be faked. Cal is still unconvinced.
Gillian and Cal visit Zach, who pins Gillian as a therapist, noting that Cal has trust issues because he knows Cal's been constantly Googling Liam. With an arrogance that barely conceals his anger, Zach produces a signed statement from Claire indicating that Kyle was due nothing, so he had no reason to kill her. Smirk.
When Wallowski tells Cal that Kyle called Claire three times on the day she was killed, Cal wants to put Kyle and Zach in the cube, but Wallowski refuses, noting that Kyle has lawyers and she has no reason to arrest Zach.
Cal confronts Kyle at a coffee shop, telling him that those corporate lawyers are useless in a murder case. Kyle describes how Zach once hacked the local cell network of a girl he liked and read her texts to get to know her better, but this left an electronic trail. Kyle believes that Zach pulled a similar stunt to frame him, which he intends to prove. He also admits calling Claire because he heard that Zach was angered by Cal's visit, and agrees to continue his work at Cal's office.
Cal finds Wallowski studying the murder scene, notices a framed photo of Claire's grandmother placed face down next to the sofa, and convinces Wallowski that Claire had sex before she was killed.
Cal asks Zach about his sexual relationship with Claire, which he denies. Gillian and Ria ask Kyle the same question, which he also denies, then admits he concealed it because he knew it would anger Zach - and would make him a more likely murder suspect - claiming that Zach's discovery of this relationship led to his firing.
Kyle locates the electronic trail and tries to trace it to Zach's ISP, which activates a hidden logic bomb that wipes out the trail.
Wallowski then asks Zach how he knew about Kyle and Claire's relationship. When he replies, "office gossip," she says that unless he can prove those two were something beyond friends, Kyle will go free.
Zach quickly heads for his computer, where Cal, Gillian, and Kyle find him checking private messages between Kyle and Claire. Kyle - who's patched into Zach's computer - points out that those were anonymous messages, and Zach's accessing them is evidence that he knew about the affair, which gives him a motive for murder.
Kyle also admits he and Claire were planning a takeover, and when Zach discovered this, he fired Kyle and forced Claire to sign those documents. Cal notes that Zach was in love with Claire, but the feeling wasn't mutual.
When Zach claims he never touched her, Gillian angrily confronts him about the knife wound. Zach sneers that all the evidence points to Kyle, and with all my money and lawyers, "the truth doesn't matter." But Cal just recorded that statement on his smartphone, and Kyle broadcasts it over a computer network.
Cal then finds that Key has invaded his office and fires him for insubordination. But Key still wants Cal to pay him for his snooping, which turned up nothing. Key says that's because Liam's a good kid, and Cal should trust Emily, adding that Cal needs to hear the truth - and Key needs a job. OK.
Cal visits Zach in jail, telling him that he's recommended Zach be put in a mental institution rather than prison. Why? Because prison will only take away Zach's freedom, but the institution's pills could take away his mind - and Dr. Gillian Foster will make sure that they do.
Cal goes home and learns that Emily broke up with Liam because he didn't believe in sex before marriage. She asks him if he loves Gillian. When Cal admits that he does, Emily asks what he's waiting for. Cal sighs, "I don't have an answer for that one, luv."