Rick Grimes returned in The Walking Dead finale and was depicted attempting to escape the CRM, only to be stopped by their helicopter-flying soldiers. Behind said helicopter was a familiar skyline featuring two famous Philadelphian skyscrapers, One and Two Liberty Place. A silhouette of the same Philly skyline was used in the first teaser for the Rick Grimes and Michonne spinoff, and the Philadelphia skyline was sighted in The Walking Dead: World Beyond when Silas talked with Jadis as he tried to infiltrate the CRM.
Interestingly, the uniform that Rick Grimes is wearing during his brief appearance in The Walking Dead series finale is almost identical to the one Silas wore when he worked at the Civic Republic's culling facility. Until now, the location of the massive Civic Republic settlement has gone unconfirmed in the Walking Dead franchise, but Rick's series finale appearance adds further weight to the increasingly likely theory that the main site is in Philadelphia. The Civic Republic's sheer size then increases the probability of the Walking Dead Maggie and Negan NYC spinoff including references to the CRM, Rick Grimes, or both.
With Maggie and Negan heading to New York City from Alexandria, they will almost certainly have to go through Philadelphia. Given the amount of crossover in The Walking Dead, more Rick Grimes teases should be expected, and this presents an opportunity to confirm to the Alexandria community that Rick is still alive. A reunion between Rick Grimes and Negan, his greatest enemy, is an enticing one, but it is unlikely that will happen in The Walking Dead: Dead City given that Rick's escape from the CRM will be the focus of his own spinoff with Michonne.
Nevertheless, Maggie and Negan may find clues pertaining to Rick's survival, similar to the boots and iPhone Michonne discovered in The Walking Dead season 10. Rick and the CRM both seem heavily tied to Philadelphia, meaning Maggie and Negan could find additional signposts left by Rick during their journey. Alternatively, the CRM may not take kindly to two strangers encroaching upon their territory, meaning Maggie and Negan may suffer their own brush with a CRM helicopter in The Walking Dead: Dead City.
