Plot

Rodney's sister is brought to Atlantis to make use of one of her theories.

Rodney McKay returns to Earth to visit his sister, Jeannie Milller, after she solves a mathematical proof that may provide for a means for transferring particles to a parallel universe. They need her help to further determine the practical aspects of her theory but she refuses to sign a non-disclosure agreement. She quite surprised to see Rodney on her doorstep given that he has not been in touch with her for four years. He manages to convince Jeannie to cooperate by transporting her to the Daedalus and soon they are in Atlantis working on the problem. There is more than just a little sibling rivalry between the two and she regales everyone with tales from Rodney's youth, not the least of which is that Rodney is his middle, not his first, name. Their attempt at transporting particles to a parallel universe goes somewhat awry when Rodney's doppleganger suddenly appears. The alternate Rodney has a somewhat different personality from the Rodney everyone knows - funny and self-effacing rather than nervous and abrupt. The experiment has caused a tear in the alternate universe and the real question becomes the alternate Rodney will be able to safely return.—garykmcd

McCay is urged by Carter to help convince his sister Jeannie Miller, who abandoned science for marriage and offspring, to resume it as a paper she produced looks like the solution for tapping into unprecedented power from subspace. Rodney must acknowledge his official first name is Meredith, and she's shown SGC, then recruited temporarily. A project on Atlantis proves her theory by creating a particles bridge, but a risk the siblings waved as insignificant comes true they reached a parallel universe, causing a ripple likely to destroy at least a galaxy. So Rodney's counterpart travels one-way to seek help in Atlantis, and proves a far more Canadian popular figure, adding to Mer's frustration. As time runs out, and the parallel world's last resort plan would shift the danger to our universe, a hasty solution must be risked, alas draining the ZPM, completely as the other Rdney is allowed to return one-way.—KGF Vissers