'Chicago Fire,' 'P.D.,' 'SVU': Why crossover episodes help networks

Not two but three TV shows will be part of an NBC crossover event that begins on April 28 with an episode of the show “Chicago Fire” and will continue through installments of “Chicago P.D.” and “Law & Order: Special Victims Unit.” 

“Chicago P.D.” debuted in 2014 and is a spin-off of “Fire,” which came on the air in 2012. “SVU” has been on the air since 1999.

According to TV Guide, the teams from each show will be working to identify a serial killer who has been committing crimes in various areas. 

“This crossover is the best [crossover] yet and provided the best episode of ‘Chicago P.D.’ yet,” “Chicago Fire” and “Chicago P.D.” producer Matt Olmstead told TV Guide. “The cool thing about this one is ... that it starts in Chicago and stays in Chicago in the 9pm hour with SVU people over there. Then, at 10, it goes to New York with our guys going there. So it plays like a 3-hour movie without ping-ponging back to particular cities for the timeslots.” 

TV show crossovers are good for network television in that they’re headline-making events in an age where cable or online-only shows are capturing a lot of pop culture buzz. At last year’s Emmy Awards, “Downton Abbey,” which airs on PBS, was the only non-cable show to be nominated for Best Drama Series (the winner was AMC’s “Breaking Bad,” while AMC’s “Mad Men,” HBO’s “True Detective” and “Game of Thrones,” and Netflix’s “House of Cards” were the other nominees). ABC’s “Modern Family” won the Best Comedy Series Emmy Award, but it and CBS’s “The Big Bang Theory" were the only network nominees with the other contenders consisting of FX’s “Louie,” Netflix’s “Orange Is the New Black,” and HBO’s “Veep” and “Silicon Valley.” Networks like CBS and ABC did do well, with their wins for "Modern" and the CBS show "Mom," among others, but NBC didn't capture any of the major awards.

In addition, the three shows involved in the crossover are some of NBC’s biggest successes, while many of their new shows are struggling. The network already announced that “SVU,” “Fire,” and “P.D.” are all renewed for next season, and the James Spader drama “The Blacklist” has been a hit for NBC. But new shows “State of Affairs” and “The Mysteries of Laura” haven’t been renewed yet, nor have the freshman shows “Constantine” or “Marry Me.” Shows “Bad Judge” and “A to Z” have already been canceled. 

And fellow network Fox recently demonstrated crossovers are still big business. According to the website Mashable, a crossover episode involving the animated sitcoms “The Simpsons” and “Family Guy” gave “Family” a season premiere that had the highest ratings in the 18-49 demographic for a premiere installment in almost four years. The crossover episode obviously brought together the devoted fan bases of each show, but it also demonstrated that shows teaming up can get big ratings.