Motive Episode 3.03 Oblivion

Angie struggles to accept Lucas's new position as primary investigator in the murder of a high-end call girl.

The Victim: Geoff Armstrong, a Scuba instructor and city planner.

The Killer: Robin Gould, an architect.

The Investigation: A crime scene in the woods reveals a blood trail and a bloody trunk of an abandoned car. The car belongs to Robin, and the blood matches her type, so the initial investigation is to find what is believed to be Robin's dead body.

The Alibi: Robin makes it look like she's dead as an alibi for committing the crime.

The Backstory: Back in college, Robin was in a serious relationship with Geoff, and the two were in a catastrophic car accident. Geoff walked away without a scratch, while Robin suffered a miscarriage and the loss of ever being able to have a child again. Their relationship ended, and Robin always remained resentful.

Though Robin had found happiness in her relationship with Isaac, her boss at the architecture firm, she felt she needed to break off their engagement because he wanted children.

Robin and Isaac were working to develop a building, but needed to work with Geoff, the city planner who had been giving them a rough time in getting the building approved. Robin went over to Geoff's office to "grease the wheels" and hopefully get him on board with their plans when she noticed that he had a picture of a sonogram hiding behind his desk. Learning that Geoff's wife is expecting a child set Robin off on an emotional tear where she yelled at him for ruining her life, and started planning her revenge.

The Symbol: Geoff has a tattoo of a crab on the inside of his wrist that he had been getting lasered off. After Robin is found alive, the detectives realize that she is wearing a matching crab charm on her necklace. Since neither one of them is a Cancer, Angie assumes that they might have had a child born in July. This symbol serves as a link between Geoff and Robin and a possible motive, so it becomes a significant lead for Angie.

The Murder: Robin goes down to the docks where Geoff teaches SCUBA diving classes and tampers with his oxygen tanks so that his death by suffocation looks like an accident.

The Motive: Robin ultimately confesses to the murder in a candid conversation with Angie, where she tells her "I was going to lose everything all over again because of what Jeff did to me." This murder is Robin's heartbroken form of revenge.

The Other Story: Maria Snow, the fiance of Robert Montgomery, London Montgomery's brother, meets with Angie a few times over the course of the episode. While at first she is trying to fish for information to see if Robert is being investigated in the murder of Derek Caster, eventually she gives Angie some very valuable information in the case.