Nickolai Stoilov

Sabrina realizes the importance of her Quizmaster after she inadvertently gets him fired.

A man breaks into Callen's house; the team discovers a shipment of counterfeit computer chips.

In an attempt to talk to Sydney, Katya Derevko deliberately poisons herself and is temporally taken out from her cell. Once Nadia tells her sister about this, Sydney visits her aunt to tell her to stay away from Nadia. However, Katya unsettles Sydney by telling her that someone framed her mother as a means of getting her killed. Sydney sets off in search of the truth behind this story. Meanwhile, Vaughn becomes a rogue agent by getting involved with the people who might know his father's whereabouts. In the end, he and Sydney find out that the man behind these two plots is no other than A. Sloane. However, things are not exactly as they seem to be.

Maura and Ali uncover new truths about their family. Shelly gets bold in her improv class. Sparks fly between Sarah, Lila, and Len and they set off to hatch a plan. Josh is haunted by the past.

With Mike away on business and Amelia at Andrea's mother's place, Andrea finds herself home alone for the first time in years and laments that she doesn't get to hang out as much with her old group of friends.