Puddle Jumper in orbit over a planet. Inside we see a young man and woman, wearing what appear to be modified Atlantis expedition uniforms.

Man: Are you sure we're in the right place.

Woman: Positive. That jump back 200, then forward 178, puts us exactly 22 before we left.

Man: Good. Try to see if you can reach anyone on the radio.

Woman: Atlantis base, please respond.

Meanwhile, inside the Atlantis control room.

Technician: Dr. Weir, we're receiving a hail. It seems to be coming from a ship in orbit around the planet.

Weir:A ship? How come our sensors didn't detect it sooner.

Technician: I'm not sure ma'am. It just seems to have appeared there.

Weir: (on the radio) Colonel Sheppard, McKay, we need you in the control room. We've detected a ship in orbit around the planet.

McKay and Sheppard come running into the control room

Shep: What's this I hear about a ship? Is it another hive?

Weir: No, actually it appears to be Ancient.

McKay: Ancient. Well, what kind of ship is it. I mean, it could just be a wraith trick for all you know.

Weir: I know that Rodney. That's why we've cloaked the city, and haven't responded to their hail.

--just as she says this the message repeats itself on the loud speakers.

Woman: Atlantis base, we know you are there. Please respond. I assure you we mean you know harm. Please, Dr. Weir, we urgently need to speak to you.

Shep: How did she know your name Elizabeth? It couldn't be the Genii could it?

Weir: If it is, why didn't they just dial us through the gate.

McKay: And for that matter, how did they gain access to Ancient technology.

Back on board the jumper

Man: I thought you said we were in the right place. Why aren't they responding on the radio. Maybe they haven't even arrived yet.

Woman: I'm certain they are there. You know Elizabeth, she's just being cautious.

Control room

Shep: Whoever it is, it doesn't seem like they're going to take no for an answer.

Weir: I agree. Patch them through. (on the radio) This is Weir, to whom am I speaking.

Woman: It's good to hear your voice again Elizabeth. My name is Amanda, and I am here with my husband Michael. I know this will be hard to understand, but we are from Atlantis, just not the Atlantis you know. Please allow us to land at the city, and we will try our best to explain everything to you.

Shep: You're not honestly going to let them land are you?

Weir: They said they are 'not from the Atlantis we know'. They might be living Ancients John. In the very least, we need to find out what they know. Send two jumpers to meet their ship and accompany it to the East Pier. Also assemble a security detail to go with us to meet our guests once they arrive. Rodney, you come along too.

McKay: Oh goody, I get to greet the potentially dangerous, possibly Ancient impersonators. That better be a large security detail Elizabeth.

Weir: (on radio) We are sending two jumpers to meet your ship, and escort you in.

Amanda: Thank-you Elizabeth. I assure you, you won't regret this.

scene with 2 jumpers guiding the third down to land at the east pier, then cut to Weir et al on the landing platform as the jumper lands

--jumper door opens, and a young man and woman exit

Amanda: It's good to see you all again.

McKay: Ok you've landed so what's up, huh. Come to, uh, sabotage our ZedPM or something.

Shep: Rodney, they just got here. Could you at least wait 'til they introduce themselves before you start accusing them.

McKay: Um, sorry.

Weir: Sorry if I don't seem to be as excited and trusting as you are, but, um who exactly are you?

Michael: Sorry, forgive us, its just…, for us we only just left most of you. You see, we are from Atlantis, just 22 years into the future.

McKay: I'm sorry did you just say future. That's ridiculous.

Shep: Rodney, you of all people should know it's possible. Remember when we found Elizabeth in stasis, and she'd been there for 10 000 years. Tell me that's not time travel.

McKay: Um, yeah, forgot about that.

Amanda: Forgive us. I am Dr. Amanda Beckett, and this is my husband, Dr. Michael Beckett. Well actually, my name before we married was Sheppard.

Shep: (to McKay) Did she just say Shep..

McKay: Yes. She did.

Shep: So that would mean?..

McKay: Either they're two other people from Earth who just happen to have the last names Sheppard and Beckett…

Shep: Or they're children of our expedition team.

McKay: Yes, well, yours and Beckett's children to be exact.

Shep: Then who are their mothers?

Michael: (to team) Sorry, please forgive my wife for not being more specific. Dr. Carson Beckett, and Lt. Laura Cadman are my parents, and Dr. Weir, you and Colonel Sheppard are her parents.

McKay: (to Shep) You and Weir?

Shep: Hey, that's what the man said. Don't ask me.

Weir: (gives a quick glance and smiles over to John, then looks back to the visitors) Ok, say we do believe you. Why did you come back here?

Amanda: I'm sorry, we've had a really long day. Would you mind if we took some time to rest before answering any of your questions?

Weir: Of course, but first I would like you to be escorted to the infirmary to be checked over by Dr. Beckett. Please, this way. (directs them off the dock)

Amanda: Of course. Thank-you.

we see Sheppard and Weir walking down a corridor of Atlantis

Shep: Are you buying their story about being our children?

Weir: I don't know. I mean, I consider us to be really good friends, but I've never really thought of having children with you.

Shep: Not yet anyway.

Weir: (smiles) Hmm. Yes, well let's just wait for Carson's DNA results.

Shep: Sounds good to me.

in the infirmary

Michael: Dad, is all this really necessary?

Beckett: Sorry lad. But we need to make sure you are who you say you are, and please don't call me dad. I know to you I'm your father, but at the moment, I haven't got any children that I know of.

Michael: Sorry, it's just, to me, we just left you, and well, I guess I thought we'd be greeted with a warmer welcome.

Beckett: Aye. Once, the DNA results come back we'll talk.

Michael: Thanks, I'd like that.

Later, in the infirmary, Weir, Sheppard and Beckett are talking

Weir: Carson, do you have the DNA results.

Beckett: Aye, and I ran them twice, just to be certain. Elizabeth, as far as their DNA is concerned, they are our children. Amanda, yours and Colonel Sheppard's. Michael, mine and Cadmann's. And there's another thing, they've both got the ancient gene. Amanda's is as strong as the Colonel's, and Michael's, is almost as strong. Elizabeth, there's nothing more I can tell you. I don't quite understand it myself.

Shep: So you're saying that Elizabeth and I will have a kid, sometime in the future.

Beckett: Aye, and not too far into the future it would seem. Both of them are 21 years old, and from what I've heard, they only traveled 22 years into the past.

Shep: Hmm, guess we'd better get busy 'Lizabeth.

Weir: (gives John the eyebrow) Thanks Carson. John, a word.

Beckett goes back to tend another patient in the infirmary

Shep: Yes 'Lizabeth.

Weir: John, I don't know if I'm completely comfortable with the expedition knowing one of our young visitors is 'our' child. Especially after all the gossip that went around after the alien-controlled kiss we shared. I mean, yes I admit that I might have feelings for you, but from what Beckett is saying, it seems like I'd have to be pregnant in a little over a year for Amanda to be 21 in the time she comes from. And I'm not sure I'm ready for that just yet.

Shep: I know. I've got feelings for you too, but, wow, a kid, that one I didn't see happening for quite a while. I mean, we haven't even had a 'proper' kiss yet.

Weir: (smirks) Yes, well John that one's up to you. (walks out of the infirmary, leaving a somewhat confused looking Sheppard)

Later in the briefing room, Weir, Teyla, Ronon, John, and Rodney are present with the two guests

Weir: Glad you are all finally here. Please now, Amanda, Michael, why is it that you've come back here?

Amanda: (motions to Michael) Please, allow me. You see, in our time the wraith have been defeated. But shortly after that, Atlantis was attacked by a new enemy. I believe you all can recall the nano-virus that infected many of the Atlantis expedition a year ago.

Weir: Yes, that virus infected almost half the expedition.

Amanda: (nodding) You see, 10 years from now a team encounters the virus on an off-world mission. It would seem that that planet had been targeted by the creators of the virus, as a sort of test site. The team came back to Atlantis, not knowing they had been infected. The moment they stepped through the gate, the city went into lockdown. But it was too late. Everyone in the control room, including yourself, Elizabeth, had been infected.

Teyla: But, the virus was designed to attack humans. Many of the expedition, including myself and Dr. Weir do not possess the ancient gene.

Amanda: (tears beginning to well up inside her eyes) Yes, I know. Colonel Sheppard, tried to detonate a naquada generator in the planet's atmosphere like last time, but it didn't work.

Rodney: That's impossible. They're machines. Machines don't take kindly to EM pulses.

Michael: The EM field had no effect on it. It would seem that the virus' creators had modified the nanites to generate some sort of EM blocking field around themselves. Rodney and Zelenka tried to find a way to stop the virus. Something that would disable the nanites, but not damage the base personnel.

Amanda: (fighting back the tears) By the time a solution was obtained, those who had originally been infected were dead. Elizabeth's death was felt hardest by John. (to Sheppard) Dad, there was nothing you could have done to save her. I know it wasn't your fault, any of your faults.

--Weir and Sheppard stand up and walk over to comfort her

Shep: But if Rodney and Zelenka found a solution, then there's a chance we can stop this from happening again.

Michael: Yes, we've brought a laptop with information on the Tenarans, the race that created the virus, as well as the gate address of the planet where the virus was encountered. But, that is not the only reason we came back.

McKay: But stopping half the city from dying from a freaky alien nightmare virus sounds like a pretty good reason to come back. What could be worse than that?

Ronon: Like you have to ask?

McKay: Um, what. Yes, yes I know there are worse things than that. But you never had that virus. Believe me, having scary, floating skull things coming at your face isn't exactly pleasant.

Teyla: Indeed.

Weir: Ok, so what other reason did you come back for?

Michael: You see, the Tenarans not only developed the virus. They were a group of Ancient who, after the wraith began their attack on this galaxy, broke away from Atlantis. They were determined to wipe out all humans in the Pegasus galaxy. The believed that if the wraith had no one to feed upon, they would leave.

Teyla: But why would the Ancients want to kill humans? They were the ones who seeded the galaxy. Gave it life.

Amanda: Yes, true as that is, these Ancients had developed a way to protect themselves from being fed upon by the wraith. If a wraith was to feed upon them, the wraith would die, and the person being fed upon would gain strength from it.

Weir: But you said the wraith had been defeated. Why would these Tenarans want to kill humans after the wraith were gone?

Michael: After many centuries away from the other Ancients, and many of them being 'infected' in a way by the wraith who fed upon them, the Tenarans grew more towards the belief that the only race who should live in Pegasus was them. They believed that the wraith would defeat their Ancient brethren and then with no food, would either starve or go elsewhere.

Shep: What I'm not buying is that these Tenarans weren't attacked by the wraith in ships. I mean, if the wraith saw them as a threat, why not just blow them up.

Amanda: The wraith had tried, on several occasions. But the Tenarans had developed great shields that could protect their planet, and would gain strength, rather than loose it, when fired upon. Much like the shields the Ori used when trying to establish their first Beachhead in the Milky Way.

Michael: These Tenarans are pure evil. The day we left, they had begun an assault on Atlantis. And in much the same way as the Prometheus was attacked and destroyed, their weapons cut right through the Ancient's shields. There was nothing we could do to save the city. McKay tried to light the engines with the 3 ZPM we had and fly the city elsewhere, but they had already been severely drained during the Tenaran attack. In a last effort to try and undo the damage that had been done, Amanda and I, ran to the flooding jumper bay and got aboard the time jumper. We came back here, and the rest you know.

Rodney: So, we all … died?

Amanda: Yes. You and Zelenka were in the lab at the time of the first strike. No one in that section survived. And, dad, the last we saw of you, you were trying to get people into as many jumpers as possible to try and evacuate. As we escaped out of the city, one final blast was shot upon Atlantis, and the city, and everyone in it was gone.

Shep: Well that sucks.

Weir: So what you're saying is that, these Tenarans can't be defeated.

Michael: Indeed. But that is why we've come back. We believe that by giving you the knowledge we have obtained early on, and preventing you from going to the virus test site, that we will greatly increase the chances that the Tenarans will not learn of the city's existence, and hence, will not come to destroy it.

Teyla: But if these Tenarans are Ancients, why would they not already know of Atlantis' existence?

Shep: I can answer that one. The city, it was sunk into the ocean when the Ancient's left for Earth. These Tenarans must believe it was destroyed, and probably only learn it wasn't because of us.

Amanda: (nods) Correct.

Weir: Ok. Rodney, you and Zelenka take a look at the data on the Tenarans. See if you can't find some sort of weakness in their technology. Something we can use if we ever encounter them. Also, Rodney, lock out the planet's address from the dialing computer.

Rodney: Of course.