The universe of Superman, Batman and Wonder Woman is coming to a clash with the universe of Doctor Manhattan, Ozymandias and Rorschach. At today’s “Spotlight on Geoff Johns” panel at San Diego Comic-Con, the veteran comics writer and architect of the DC Universe in comics (and beyond) shared several key details on Doomsday Clock.

Very little has been known about Johns’ upcoming series, drawn by Gary Frank with colors by Brad Anderson, which isexpected to make good on the most shocking promise of DC’s Rebirth relaunch. It likely features Superman and Doctor Manhattan, and its first issue will be released in November of 2017 — and now we know a bit more.

Perhaps the biggest news is that Doomsday is no mere short crossover or one-shot, as previous "main story" Rebirth events —Rebirth #1 andThe Button — have been. Instead, it will be a year-long, 12-issue series, set one year into the future of the DC Universe.

In that way, by the time Doomsday Clock releases its 12th issue, the rest of the universe will have caught up to it — and the repercussions of the event will become known.

As a way to both tease the audience and prompt Johns to reveal details on the story, DC’s co-publisher, Dan Didio, had him play a sort of word-association game with individual panels from the first issue of the series. For example, when a panel of a car whose occupants had clearly left in a big hurry appeared on the projection screen, Johns said “desperation.”

After considering a image of a city skyline crowned with the iconic globe of the Daily Planet building, the writer said “Superman.”

“Is he integral to the story?” DiDio asked, with characteristic coyness.

“He is the story,” Johns answered, immediately.

The final image that DiDio showed off appeared to be a splash panel of the entire Justice League, Wonder Woman foremost, under the repeated refrain of Watchmen: “Who watches the watchmen?”

To cap off the panel, Johns said that one of his favorite scenes in the series so far came about from asking: What would happen if the smartest man in the DC Universe met the smartest man in the Watchmen setting? While all signs have pointed at Doctor Manhattan being a major player in Rebirth’s plot, there are more Watchmen characters in the mix than just him.

The smartest man in the DCU, Johns said, is Lex Luthor, leaving it up to the audience to fill in the blank — but undoubtedly indicating Adrien Veidt, or Ozymandias, a major player in the plot of Alan Moore and Dave Gibbons’ Watchmen.

Doomsday Clock debuts on Nov. 22.