McKay will meet his rival

Beware of minor SPOILERS for the fifth season of Stargate Atlantis in the report below.

The upcoming fifth season of Stargate Atlantis will give fans a look into Rodney McKay‘s past — specifically, one of his rivals. Executive producer Joseph Mallozzi talked about the idea in a new fan Q&A at TVGuide.com.

“Indeed we will [see more of Rodney’s past], in a late Season Five episode in which he’ll be reunited with an old friend and rival,” Mallozzi revealed. “We’re casting this one as I answer this question and, if all goes as planned, it will offer up some fun cameos.”

The episode in question is still unknown, but it is almost certainly after “Remnants” (episode 15) and before the season finale. “Brain Storm” is a likely candidate, based on the title (the brilliant McKay reunited with a brilliant rival from his past) and the fact that Mallozzi said the episode is currently in the casting phase.

“Brain Storm” is sixteenth in the production order, and is expected to begin filming in August.

Mallozzi also offered a hint in regard to the season finale, which will mark the one hundredth episode of Stargate Atlantis. “We’ve yet to break the one hundredth episode. However, in our initial spinning, we have discussed the possibility of having the best of both worlds — or galaxies, as the case may be.”

Do we smell a crossover?

The producer also said that the recurring Wraith character Todd (Christopher Heyerdahl) will appear in “at least five episodes” this season. Paul McGillion (“Carson Beckett”) will also appear in five episodes, as previously reported, and Kate Hewlett (“Jeannie Miller”) will return to guest star in “The Shrine.”

Check out the full Q&A now at TVGuide.com. Stargate Atlantis launches into its fifth season on Friday, July 11 at 10 p.m. (9 Central) on SCI FI Channel.