|Harper's Island episode|
|Episode no.|| Season 1|
|Original airdate||July 11, 2009|
|List of Harper's Island episodes|
The episode begins with a flashback to 16 years before. A young Henry and Abby are playing with their toys, when Henry's parents arrive to collect him. It's the end of summer and they have to leave the island. Abby and Henry run down to the beach, where Abby whispers something into his ear and Henry agrees with her, and says goodbye.
In the present day, Henry tells Wakefield that killing Trish was harder than the others,because he cared for her. Wakefield tells him that Danny’s death wasn’t an embarrassment. Henry tells his dad that they only have a couple hours before the Coast Guard arrives so they leave.
Shea and Madison arrive at the boat house and tell Sully that Wakefield escaped and killed Danny. Sully takes a boat from the rafters and makes Shea and Madison leave, staying behind himself. Henry meets up with Sully at the boat house, where the coast guard tells them to meet at the marina in 45 minutes. The two leave to find Trish, and Henry confesses to all the murders he committed. He also tells him that the money they found was actually Uncle Marty's, who wanted to invest in Malcom's brewery. Sully thinks it's all a joke at first, but when he realizes it's true, he tries to shoot Henry but fails. Henry reveals he removed the bullets back at the boat house, and with Wakefield watching, he kills Sully.
Henry then finds Jimmy and Abby, who tell him that Trish is dead. Henry demands to see her body, but when they return to where he killed her, her body is gone. Pretending to believe she is still alive, Henry lures Abby and Jimmy to the church, where they find Trish's body laying on the altar. Wakefield surprises them from behind and attacks Jimmy. Jimmy tells Abby to run. As she leaves, Wakefield screams at Henry that she's getting away, and Jimmy realizes that the two have been working together. He starts up his flare and uses it to burn Wakefield in the chest before throwing it at the unity candles making the wooden support catch fire. As Jimmy tries to leave the church, Henry shoots him in the back, incapacitating him. Henry finds Abby and tells her that Jimmy is dead. As they make their way to the marina, Abby begins to realize that Henry's story doesn't add up. When she calls him on his lie, he pulls out his switch-blade. Unaware that Wakefield is behind her, she steps away from Henry. Instead of killing Abby, Henry pushes her away and kills Wakefield. Realizing that Henry was the second killer, Abby tries to run but Henry knocks her out.
A few days later back on the mainland, the FBI tell Shea that all the others she left behind died in the church fire, including Wakefield. Aside from a few locals, Shea and Madison are the only survivors.
Back on the Island, Abby awakes in a strange house, where she finds Henry. He tells her that he chose her over his father. Wakefield wanted to kill Abby but Henry loved her and couldn't do it. Abby tries to escape but all the doors are locked, so she retreats back into the room she woke up in. On the other side of the door, Henry reminds her of what she told him 16 years before. "I wish you could live here forever, just the two of us." He tells her that now they can.
Later, Henry goes to check on Abby, but finds her threatening him a large piece of broken glass. She demands to know how he could do all of this and Henry tells her how he came to know Wakefield. She uses a telescope to break through a glass door and runs into the garage, where she finds Jimmy alive and bound. Henry then explains his plan: He will make Jimmy sign a confession claiming to be Wakefield's accomplice, since Shea and Madison got off the Island.
Back in her room, Abby tries to use a wall hook to pick the lock, but fails. When Henry takes her to say goodbye to Jimmy, Abby goes to Jimmy and kisses him, passing him the wall hook through the kiss. As Henry pulls her away from him, she tells Henry that she loves Jimmy and he slaps her, knocking her to the ground. Abby grabs a screwdriver from the floor and stabs Henry through the foot, then runs away. Henry goes after her with a boarding knife, until she reaches a cliff. Telling her that he could never hurt her, he tries to prove it by throwing the knife over the cliff. He tells Abby that he would die without her. She tells him that he has destroyed everything she ever loved, to which he replies that she has him, but she shouts back that she doesn't want him. Jimmy then runs up behind Henry and tackles him, and they both fall off the edge.
Abby runs down to find that Jimmy is ok, just as Henry slowly approaches behind her. Abby grabs the nearby boarding knife and stabs Henry with it. With his last breath, he tells Abby he loves her, and dies. Abby and Jimmy are rescued by the coast guard,and are seen leaving the island together. 
The episode ends with previous recordings from the wedding guests while on the boat before they went to the island, these include clips of Abby, Trish, Chloe, Cal, Sully, Booth and Malcolm. Henry's is the last to be shown as he tells Trish that he can't wait to be married to her and he then smiles to the camera as the screen fades.
- Christopher "Sully" Sullivan - stabbed in the back by Henry
- John Wakefield - stabbed in the heart by Henry
- Henry Dunn - stabbed in the chest with a boarding knife by Abby and gives a short sigh before he dies
- Elaine Cassidy as Abby Mills
- Christopher Gorham as Henry Dunn
- Jim Beaver as Sheriff Charlie Mills
- C.J. Thomason as Jimmy Mance
- Matt Barr as Christopher "Sully" Sullivan
- Sarah-Jane Redmond as Sarah Mills
- and Callum Keith Rennie as John Wakefield
- Gina Holden as Shea Allen
- Cassandra Sawtell as Madison Allen
- Ava Hughes as Young Abby
- Alex Ferris as Young Henry
- Ryan Grantham as Young J.D.
- Adrian Hough as Frank Dunn
- Nadine Wright as Karen Dunn
- Kweski Ameyaw as FBI Agent Hanson
- Barbara Kottmeimer as Agent Ana Perez
- Peter Ciuffa as Man in Seattle
- Katie Cassidy as Trish Wellington
- Cameron Richardson as Chloe Carter
- Adam Campbell as Cal Vandeusen
- Brandon Jay McLaren as Danny Brooks
- Chris Gauthier as Malcolm Ross
- Sean Rogerson as Joel Booth