The One Chicago Star With The Most Crossover Appearances

NBC's "One Chicago" universe of hour-long dramas focuses on various groups of people helping to polish up the city's civic pride — from police officers patrolling Chicago's mean streets to doctors treating whose who get hurt on said streets. The universe is comprised of "Chicago P.D.," "Chicago Fire," "Chicago Med" and the short-lived "Chicago Justice."

The three dramas have a lot of crossover action going on, and the fact that all of them shoot in Chicago and in the same studio makes it a breeze to shift characters between sets. Ergo, characters from all three shows tend to crossover a lot, to the point of sharing major life events, important relationships, and backstories. Characters in the "One Chicago"-verse have dated one another, and there have even been cross-program marriages — most notably, between "Chicago P.D." star Trudy Platt (Amy Morton) and "Chicago Fire" star Randy "Mouch" McHolland (Christian Stolte). Some of the characters are even related by blood, such as Will Halstead (Nick Gehlfuss) of "Chicago Med" and "Chicago P.D." star Jay Halstead (Jesse Lee Soffer), who are brothers.

But which "One Chicago" actor has racked up the highest number of miles crossing town and popping up in programs where they don't regularly star? Who's the king (or queen) of the crossover episode? Here's what we've determined.

As of press time, Jon Seda, who portrayed Antonio Dawson on "Chicago P.D.," has racked up the highest number of "One Chicago" universe crossover episodes. He popped up a whopping 47 times on "Chicago Fire" — where Antonio recurred and often visited his sister, Gabriela "Gabby" Dawson (Monica Raymund) — and made 13 appearances on "Chicago Justice" for a grand total of 60 appearances on other "Chicago" programs. Even though Seda left the "One Chicago" universe in 2019 and is now a regular on NBC's "La Brea" (per IMDb), this is a huge record.

In second place is Jesse Lee Soffer. Jay Halstead has appeared on "Chicago Med" 28 times (often interacting with his aforementioned brother, Will), and 18 times on "Chicago Fire," placing him behind Seda at 46 episodes. Rounding out the top three, Nick Gehlfuss trails Soffer with 37 appearances, 20 on "Fire" and 17 on "Chicago P.D.". 

Will anyone be able to one day topple these records? "One Chicago" fans will have to keep tuning in to find out, but Seda leaves quite a record to beat.