Opens to the tune of “Three Blind Mice.” The Titan hides in the Chin’Toka Scrapyard.

On the bridge, Seven discusses Riker whereabouts with Tuvok. T’Veen runs audio scans on Tuvok’s voice to try to see if he’s a changeling. Seven tries to suss it out through carefully worded questions.

Frontier Day is 36 hours away.

T’Veen and Shaw’s voice analysis proves inconclusive. Seven seems heartened when Tuvok references their games of kal-toh and the many times she’s beaten him. Tuvok suggests they meet so he can help find uncompromised allies.

Seven suggests meeting on Aklian-7 where she once had her neural pattern stabilized. Tuvok agrees. Seven points out that a Vulcan would never go to Aklian-7 after the anti-kohlinar demonstrations. Furthermore, her neural patterns were stabilized by the real Tuvok through a mindmelt on Voyager.

With the charade revealed, the changeling grins and promises death will be a relief when they are done with their enemies. Picard demands to know where Riker is. The changeling shifts to a horrifying visage of Riker, commenting he’s good as dead. Geordi cuts the communication link before they can be traced.

Picard realizes they’re on their own.

Part Seven: Dominion

In the ready room, Picard, Geordi, and Beverly collaborate on a plan. Geordi reports that Worf and Raffi are monitoring Starfleet Security chatter. There’s been no report of Riker in custody.

Beverly suggests that the new changelings who have attacked them are unique in come fashion and they can target that uniqueness to target, identify, and expose them.

The solution would be based on biological markers, something that skirts close to genocide.

Picard recalls that he was meant to be a part of Frontier Day and, as a fleet admiral, there would’ve been genetic confirmation of his identity required. Geordi puts that information together with the remains stolen from Daystrom and hypothesizes the changelings are trying to create a perfect Picard doppelganger.

Knowing they need more information, they go to see Data. They activate the cognitive functions to talk to him but Lore quickly takes over. Geordi explains how both Data and Lore’s programs are simultaneously existing in this body along with Soong and B4.

Data and Lore’s programs are partitioned but they are battling for dominance. Picard tries to appeal to Data to explain why the changelings stole his body. Data calculates and reveals there was an anomalous form found in the human remains of Picard and that the previous diagnosis of Irumodic Syndrome is in question.

Before Data can explain further, Lore comes to the front again, refusing to help them. Data manages to ask for help. Picard orders Data shut down.

Picard asks Geordi if they can free Data by erasing Lore. Geordi worries that lifting the partition may allow Lore to completely destroy Data’s programming.

On the Shrike, Vedic reports to her handler that Picard’s associates remain loyal and she doesn’t expect they’ll get any information from them. The handler refuses and threatens her if the changelings do not have Jack in time for the Frontier Day plan to work.

On the turbolift, Jack and Sidney find themselves alone. He flirts with her and then can suddenly hear her thoughts.

When he acts on something she thinks and touches her hand, she’s startled and leaves the lift, stopping to ask why he did that. Jack experiences another vision and can’t answer.

Jack goes to see Picard on the bridge. Just as he arrives, a trace signal from Starfleet is detected and it’s identified as Riker’s compromised prefix code, used to signal a starship that he’s been captured.

Jack shares his conflict with Picard. He proposes that he give himself up to the Shrike to get Riker back. He tells Picard he thinks there’s something wrong with him, that he’s hearing things.

When Picard urges him to not give up, Jack points out they’ve never had an advantage. Picard thinks of something and suggests they actually do.

In Open Space in the Alpha Quadrant, the Shrike finds the Titan, seemingly inoperative. The Shrike detects a subspace recording, indicating the Vulcan warship engaged the Titan and incapacitated both ships in the battle.

Vadic orders a boarding party to shuttle over. One of the crew urges caution, but she’s insistent.

Vadic leads the boarding party. Jack walks up to tell her everyone’s dead. She corrects him that not everyone is dead and she wants to take him to a better place.

He challenges them to catch him first and runs. Vadic sends crew in pursuit. Jack and Sidney fire on the pursuers.

They lure the Shrike crew into separate spaces and drop pre-arranged forcefield barriers to trap them.

Jack finds himself cornered by Vadic in sickbay. He orders the next barrier dropped and Vadic is caught.

Running out into the corridors, he and Sidney find each other and when the next barriers are activated, they are safe but effectively trapped as well.

Geordi is about to transport Jack and Sidney out, but the transport direction is denied. He and Alandra go to investigate and the chamber shuts behind them. Lore has reactivated himeself and taken control.

Beverly approaches Vadic to talk to her. Vadic is whistling snatches of “Three Blind Mice” and seems at ease.

Beverly tries to threaten Vadic to talk, but she isn’t intimidated. Picard joins them and tries to question her.

Vadic hints that Jack’s physiology is unique. Beverly demands to know what they want with Jack. Vadic is cagey.

Picard tries to open a dialogue regarding the history of the Dominion War. Vadic informs them that the cure created for the changeling virus was withheld by a vote of Starfleet. A changeling had to steal it to get it to the Great Link. Vadic continues and tells them her hatred came from Starfleet because it was Starfleet scientists who gave her the ability to mimic so profoundly and to hold her form.

Her evolved physiology is the result of painful, inhumane genetic experiments.

The Shrike crew trapped with Jack and Sidney try to break through the barriers. Geordi reports that Lore has taken over all major systems.

Vadic is lost to her memories, conducting the music in her head. She asks Picard and Beverly if they like the symphony. She explains that she learned about solids while imprisoned at Daystrom Station. It’s where she learned about music.

She and nine other changelings were used for Project Proteus. The scientist in charge would whistle while she performed terrible experiments on the changelings in their liquid forms. The purpose was to turn them into weapons for the Federations, the perfect spies. Vadic wears her face as a solid.

Vadic explains she is able to pass on the abilities she gained from those experiments to anyone willing to join the cause of bringing down the Federation.

Sidney informs Geordi the shield regulators are failing. Geordi tries to reach Data, but Lore insists he’s overpowered his brother and he’s of no use to Geordi.

Beverly and Picard realize Vadic is a danger to Jack and they agree to kill her together before she can escape.

Geordi speaks to Data about his influence on Geordi and his life, saying what he never got to say when Data died the first time.

Lore manages to keep Data subdued and explains to Geordi that he simply wants to survive. He tells Geordi he’s about to level the playing field. He lowers all shields around the ship, releasing Vadic and her soldiers.

Vadic assumes liquid forms and escapes. A force field appears between Jack and Sidney, forcing them to take on the Shrike crew members on their own.

As they fight, Geordi begs Data to help. Jack manages to get a weapon and disintegrate the soldier he’s fighting. Sidney’s soldier is overpowering her and preparing to kill her.

Jack uses his new telepathic abilities to help Sidney win the fight. Geordi continues to plead for Data to open the door and help him. Suddenly, the door opens and Data assures Geordi that he’s there.

Data accesses the field regulators and lowers the force field separating Jack and Sidney. Sidney’s in shock, having been mentally puppeted through the fight.

Sidney draws her weapon on Jack, freaked out by his new ability. Jack sees Vadic approaching and grabs Sidney’s hand, insisting they run.

Beverly uses the information Vadic gave them to figure out the formula the captive changelings were exposed to, tholonium-847, a stabilizing agent with a hundred year half-life.

Using that information, they are able to track the changelings aboard the Titan. Picard contacts Shaw and lets him know Vadic and her soldiers are heading for the bridge. Shaw and a security detail engage Vadic and a lone changeling soldier. Shaw’s detail is taken down. The soldier is dropped by Shaw’s fire but jumps up once Shaw passes to trap him between him and Vadic.

They throw him into the turbo lift to shield them as they breach the bridge.

Vadic’s soldiers overwhelm the bridge crew and they assume control. She opens a channel and addresses the ship. She takes a seat on the Titan, declares herself captain, and lets Jack know the time has come to learn who he truly is.