Fox is staging a crossover for “New Girl” and Brooklyn Nine-Nine.” The hourlong event will air Tuesday, Oct. 11.

The crossover was announced Monday at the Television Critics Association press tour at the Beverly Hilton in Beverly Hills, Calif.

“’Brooklyn Nine-Nine’ crossing over with ‘New Girl’ is very exciting, but (and this is supposed to be a secret) it’s just the first step,” said Dan Goor, co-creator and executive producer of ‘Brooklyn Nine-Nine.’ “Stay tuned for our two casts to do a soulful R&B number on ‘Empire’, co-anchor the Fox 10 O’Clock News and connect for a touchdown on Fox NFL Sunday. But in all seriousness, we’re all huge fans of ‘New Girl’ here at the ‘Nine-Nine,’ and we’re excited to see our characters interact and to work with their incredible writers and producers. And also to see what their craft services are like, compared to ours.”

“The crossover episode has historically been the artistic high point of any show that has dared to attempt it. Maybe you remember ‘Blackout Thursday’ on NBC, or even further back the infamous ‘Alf’/‘Gilligan’s Island’ crossover of the late 1980s. ‘New Girl’ and ‘Brooklyn Nine-Nine’ will proudly and humbly go where few shows have gone since the 1990s. We know we have big shoes to fill, and we look forward to disappointing everyone. There’s a 50% chance Alf will also be in both episodes. But there’s also a 50% chance that is a lie,” said  Elizabeth Meriwether, creator and executive producer of ‘New Girl.’

Plot points and more crossover details will be revealed at a later time.

Also announced Monday at TCA is the first-ever hourlong episode of “The Simpsons,” which is set to air in January. The episode titled “The Great Phatsby” will feature voice guest spots by “Empire’s” Taraji P. Henson and Keegan-Michael Key.

“I just pray it won’t be the last thing people see before a Trump inauguration,” said executive producer Al Jean, of the one-hour episode.