Bloodlines

"Bloodlines" is the sixth episode of the second season of Young Justice, and the 32nd of the overall series. It aired on June 2, 2012.

Logline
An intruder mysteriously appears inside Mount Justice, claiming to be a tourist from the future. But who is he really? And what is his true agenda?

Synopsis
In a world darkened by an ash rain, a bald man checks up on a boy, who's working on a machine. The man wishes he could come along, but the machine only seats one.

Nightwing examines Krolotean data as Robin and Beast Boy enter, greeting him. Nightwing explains that the Kroloteans were looking for something inside their human captives that the nearest English translation for is "meta-gene", and no one knows what that means. The computer detects an energy impulse, and in a ball of lightning, a machine appears in the room. The boy from before comes out, and takes the name Impulse after Beast Boy identifies the machine as the cause of the impulse.

"Impulse" runs amok in the Cave, and Nightwing sends the two junior members after him. He first loses Beast Boy in the showers, and then Robin in the kitchen. He runs back to the Mission Room, and thinks he's outsmarted Nightwing's marbles on the floor. As he relaxes, Nightwing flanks him and subdues him. He's given cuffs on his wrists and ankles.

Impulse introduces himself as Bart Allen, but his claims, that he is from the future and the grandson of Flash, are initially not believed. Nightwing gives him a glass of water, but Impulse knows that he only wants his DNA. He freely offers it, and "spoils" the secret identities of Robin and Nightwing to Beast Boy to prove he's really from the future.

Mal arrives, giving Impulse the cue to break free and escape. Beast Boy transforms into a peregrine falcon and gives chase, though Nightwing and Robin doubt he'll keep up. It would not be necessary, as Nightwing had taken the precaution of placing a subcutaneous micro-tracker in the water, and traces it to find that Impulse is heading to Central City. This leads Nightwing to call and ask someone for help.

Cheshire and Red Arrow are standing on ledge across from the building they need to enter. Red Arrow is skeptical of Cheshire's motives, given that the "good guys" have been searching for the real Roy Harper for years and Cheshire suddenly has a lead. Cheshire counters this by saying that she goes where good guys won't. She says that Lian needs Red Arrow to put his "Real Roy guilt" behind him to be able to be a good father to her. Roy checks up on Lian, who's safe and warm in Jade's backpack.

They then proceed to break into their destination with Arrow sliding down a zip-line, knocking the guard out, and Cheshire following afterwards. They continue to break through the enemies defences, but after knocking several guards out, Lian blows their cover by cheering. This causes guards to surround them and Arrow to quip that they should have left her with Cheshire's sister.

Barry, Iris, Joan and Jay are celebrating Joan and Jay's 70th wedding anniversary when Barry gets a phone call from and is told about Impulse. Impulse promptly arrives at the house, proclaiming that he is Barry's grandson and proceeds to hug everyone in the room. Barry refuses to accept it, because he and Iris don't even have kids. Iris cuts him off by saying that she's pregnant—she found out this morning—causing Impulse to hug her belly, saying hello to his dad and aunt. This revelation shocks Barry and Iris. Wally arrives, causing confusion and surprise in the house guests. He remedies this by saying that Nightwing gave him a call. Impulse hugs him.

A phone rings and Barry, thinking it is his, checks his phone. It turns out that it is Iris's phone and Impulse, knowing that Flash is meant to die, tries to stop her answering her phone. She answers her phone and informs Barry of a new super-powered supervillain. Bart tries again to dissasaude Barry from dealing with it but fails. Barry changes into his costume and heads to the commotion. Wally looks at Bart and knows full well that he won't stay put.

At a Central City square, the Flash tribute statue is destroyed by the new super villain. He walks through Central City leaving a trail of destruction, releasing circles of energy within seconds of each other. Civilians are running from the danger and a woman and child are nearly caught in a blast, but the Flash whisks them to safety and tells them to take shelter at Fox and Gardner.

Flash goes into the middle of the danger and gets hit by a circle of energy, and is thrown clear. Impulse causes a wind funnel to catch him before he hits the ground. Flash is impressed and Impulse says that his dad will learn it from him. Flash then questions Impulse on what he's doing. Impulse answers that he wanted to see Flash in his prime and also gives the villain's name—Neutron—and covers his slip by saying that the villain was saying it all the time.

Kid Flash talks to a police captain for an update. Impulse and Flash dart over and Flash tells the captain that the best he can do is keep civilians away from danger. Flash and Impulse discuss strategy: they'll create a funnel to contain the villain. As they talk, their speaking speed increases, and Kid Flash can't keep up. Impulse explains that he should just follow them.

Flash, Impulse and Kid Flash make a wind funnel, trapping Neutron inside and causing him to rise into the air. This causes the energy blasts to rise with him where they can make no harm. Two mysterious aliens, who were controlling Neutron from a warehouse elsewhere in the city, monitor their subject. Neutron's suit is destroyed by the explosion caused by the wind funnel. Flash and Impulse have to drag Kid Flash away from the blast.

At a safe distance Kid Flash activates his goggles and scruntizes the energy coming from Neutron and says that he seems to be disappearing. Flash asks for the goggles and Wally hands them over. Flash says that Neutron is about to explode again and says that he needs to get him to a desert to save the city. Impulse follows him and trips him before he can get caught in the explosion. Neutron explodes, but Kid Flash and Jay Garrick carried Flash and Impulse to safety. Flash admits that he would not have reached the desert in time.

Impulse goes back to Neutron and drops a pill causing Neutron to return to normal. When the speedsters arrive Bart says that he doesn't know how Neutron went back to normal.

Back in Tibet, Cheshire and Red Arrow have knocked every guard out that was opposing them, causing Lian to laugh. Red Arrow asks Cheshire if he should be worried about their daughter's obvious delight in violence. Cheshire replies that it's genetic. They open the door in front of them, and in a cryogenic pod, they find the real Roy. Unconscious, he falls into Red Arrow's arms. Lian recognizes him, and laughs "Dadas!".

Back at Mount Justice Impulse is saying goodbye to everyone and says that it "has been crash". He gets in the time machine, but it doesn't work. Bart knows why and covers it up by saying that the circuits are fried and that he's stuck in the past, seemingly frustrated at the prospect.

Bart is working on the time machine when the bald man, Nathaniel Tryon, comes to him, asking him if he's finished. He tells Bart that going back in time to save Flash's life was just the beginning and time traveling to 2016 will fry the time machine, making this a one-way trip. Bart sardonically asks if Tryon feels that this was a place worth coming back to and changed into character. Nathaniel gives him a pill that would remove his past powers as Neutron, and Bart heads off to do his mission.

As the time machine disappears, so does the scar on Nathaniel's face, and the inhibitor collar around his neck. He is shocked to realize that Impulse saving Flash's life did not change anything else; the world is still in ruins.

Title
The term "Bloodline" is used to describe a family connected by blood. This applies to Bart meeting his grandfather and grandmother from the past. Also, it may refer to Red Arrow finding Roy Harper, whom he was cloned from.

Cast and characters
! colspan="3"| Non-speaking roles
 * Cameron Bowen
 * colspan="2"| Robin
 * Nicole Dubuc
 * colspan="2"| Iris West-Allen
 * George Eads
 * colspan="2"| Barry Allen/Flash
 * Crispin Freeman
 * colspan="2"| Red Arrow
 * Logan Grove
 * colspan="2"| Beast Boy
 * rowspan="2"| Kelly Hu
 * colspan="2"| Cheshire
 * Lian Nguyen-Harper
 * Stephanie Lemelin
 * colspan="2"| Computer
 * Jason Marsden
 * Bart Allen/Impulse
 * Jesse McCartney
 * colspan="2"| Nightwing
 * Geoff Pierson
 * Jay Garrick/Flash
 * Jason Spisak
 * colspan="2"| Kid Flash
 * James Arnold Taylor
 * Nathaniel Tryon/Neutron
 * Jason Marsden
 * Bart Allen/Impulse
 * Jesse McCartney
 * colspan="2"| Nightwing
 * Geoff Pierson
 * Jay Garrick/Flash
 * Jason Spisak
 * colspan="2"| Kid Flash
 * James Arnold Taylor
 * Nathaniel Tryon/Neutron
 * Jason Spisak
 * colspan="2"| Kid Flash
 * James Arnold Taylor
 * Nathaniel Tryon/Neutron
 * James Arnold Taylor
 * Nathaniel Tryon/Neutron
 * colspan="3" | Joan Garrick
 * colspan="3" | Mal Duncan
 * colspan="3" | Speedy
 * colspan="3" | Mal Duncan
 * colspan="3" | Speedy
 * colspan="3" | Speedy

Continuity

 * Nightwing mentions the data Miss Martian and Martian Manhunter downloaded on Malina Island, as shown in "Alienated". Beast Boy didn't know because he was not there.
 * Cheshire explains the lead that she revealed she had on Speedy in "Salvage".
 * The police captain gets Kid Flash confused with Speedy, just as a spectator did in "Independence Day".
 * Kid Flash remarks he's used to being lapped by the Flash. This was first seen in Young Justice #16: "Common Denominators".
 * Red Arrow finally finds Speedy after five years of searching, which started in "Auld Acquaintance".

Trivia

 * Flash mentions a shelter on "Fox and Gardner", a reference to one of Jay Garrick's creators, Gardner Fox.
 * This is the first episode in which Miss Martian is absent since her debut in "Fireworks".
 * Impulse twice says, "Oops, spoilers" when discussing the future. The line is often heard in the TV series Doctor Who, spoken by River Song, a companion from the Doctor's future, when she is concerned about saying too much about the future.

Goofs

 * When Robin asks Impulse if he's really from the future, his "R" insignia is missing.
 * Right after Red Arrow and Cheshire land on the bell tower, Red Arrow has a gauntlet on the arm facing the screen, but in the next shot, it is a glove.
 * When Impulse is given the pill to cure Neutron before leaving the future, his goggles are on, but in the next shot, they are off and he is seen putting them on.

Cultural references

 * Impulse mentions that "...half the meat at Comic-Con are from his era." Comic-Con International is an annual comic-book and pop culture convention.

Unanswered questions

 * What is a Meta-Gene?
 * Who were the aliens controlling Neutron?
 * What caused the future to turn out the way it did?
 * Why wasn't Impulse's apocalyptic future completely subverted when he fulfilled his mission?
 * What does "crash the mode" mean?