The typical process to bring a TV series to audiences begins with shooting a pilot episode and screening it for studio executives. They will decide to send the show to series, and film more episodes … or they set it loose into the unknown, never to be heard from again. Furthermore, sometimes the pilot episode of a longstanding series can look insanely different from what fans come to know and love. Everything from different sets to new actors can completely feel unrecognizable to an audience. For example, did you know there was a pilot episode shot for “Full House” with someone other than Bob Saget as Danny Tanner? It may feel completely foreign to think of anyone other than Saget, but the first actor to play the role in the pilot was John Posey.

The long-running police drama “Blue Bloods” is in the middle of its 12th season, and by now, the actors and sets are burned into the fans’ memory. However, some things from the pilot episode feel entirely out of place when viewed after over a decade. Here are five things that fans may not have noticed in the pilot.

Jamie’s got a new girl

At this point, it is hard to imagine Jamie Reagan (Will Estes) was ever romantically involved with anyone other than partner-turned-fiancé Officer Edit “Eddie” Jenko (Vanessa Ray). However, if you rewatch the pilot episode today, you’ll be shocked to remember that long before Jenko arrived on the scene as his new partner in Season 4, Jamie was engaged to the brainy brunette, Sydney Davenport (Dylan Moore).

Unlike most of the differences in the pilot episodes, this one has a storyline spanning five episodes. One core characteristic of Jamie Reagan has been his decision to join the police academy once graduating law school: this occurs after his older brother’s untimely and suspicious death on the job. Sydney is immensely supportive in the pilot episode — when she is around the Reagans, at least — but there is an evident tension between them as she clearly isn’t entirely comfortable with her fiancé’s decision. Ultimately, being the wife of a police officer is more than she can handle, and when the pair call off the wedding, she moves on with her life without him.

Kitchen got a remodel

One of the most vital aspects of a TV series that viewers often overlook, when reminiscing about their favorite shows, is the importance of set. Once a series ends, the sets can become cultural icons. For instance, who doesn’t remember the fictional coffee shop Central Perk from “Friends,” or Jerry’s apartment in “Seinfeld,” where all the hijinks and conversations take place? And when it comes to “Blue Bloods” there might be no set more important than the place where all those beloved family dinners are made.

In the “Blue Bloods” pilot, though, that particular set isn’t quite what you’d expect. For one, the kitchen is smaller. Two, it has white cabinets, and throughout the rest of the series, the color scheme changed to a more comfortable brown color.

No explanation was given for the change. Maybe it felt a little homier, or the deeper color felt more appropriate for the dark themes in the show, or the set may have just been completely rebuilt once the series was ordered. In any case, the kitchen has proven to be a vital part of the show. In some ways, it became a character of its own. This is where the family spends their time bonding, razzing, or debating each other. How many times have viewers seen two characters in the kitchen and known what was about to happen?

Nikki was played by a different actor

Recasts are a fact of life for most TV series or movie franchises, whether it is due to a conflict of interests — see, the case of Terrence Howard, who played James “Rhodey” Rhodes in the MCU before Don Cheadle took over — or an actor moving on to bigger and better things. On television, some of the bigger recasts happen from the pilot to the series, primarily due to time passing between shooting the pilot and filming the rest of the episodes.

This kind of switch took place with the character of Nicky Reagan (Sami Gayle). While Gayle has become the face of the younger generation of Reagans, the pilot episode offered the character with a different … well, face. The first actress to play Nicky was a young actress named Marlene Lawston. There isn’t much out there on the reasoning for the switch, and since the actress’s IMDb page shows no other activity following her brief role on “Blue Bloods” — over a decade later — we can probably assume that she moved on from acting to pursue a different avenue in life.

Henry’s leg was healed

Len Cariou knows what he is doing. He is a brilliant actor that understands good theater and good character when he lays eyes on it. If you need some proof of that kind of brilliant foresight, just take a look at his incredibly daring and award-winning performance of the very first “Sweeney Todd” in the late 1970s (per PlayBill). Taking that brilliance and foresight to “Blue Bloods,” he landed the role of patriarch Henry Reagan.

While Cariou’s performance in the pilot was as strong as ever, though, the character was a bit different — namely, he walked with a cane, a facet that is noticeably missing from the rest of the series. As a matter of fact, he is shown to be a remarkably spry man for his age, later on, as the series shows him continually getting involved with police matters. The reason for the cane and the limp given in the first episode is a hip replacement. The cane goes away immediately afterward, and is never spoken of again.

Given that Henry is the head of the Reagan family, his constant show of strength and resolve are a major part of his character. And in some ways, even if he was supposed to use a cane, you could expect his Reagan stubbornness to keep him from doing so … much like it keeps him from giving up his driving privileges in later seasons, when he is questioned about continuous scrapes to the car.

Frank had a girlfriend

In the pilot episode, there are two surprising similarities between Frank Reagan (Tom Selleck) and his youngest son, Jamie. The first similarity is that they are both in relationships. The second, unfortunately, is that neither of them works out.

Jamie’s fiance leaves him because his job is more than she can handle. His father’s relationship, though, comes to an end due to betrayal.

Similar to Jamie, Frank’s relationship is a storyline that plays out on screen, though the latter sees his love life come to a halt within the span of one episode. In the pilot, Frank’s girlfriend, Kelly Davidson (Andrea Roth), is a reporter who turns out to be using him for leads to big stories. Frank is pulled away during the episode, and Kelly assembles her news team, arriving at the crime scene before the police. After this, Frank understandably ends the relationship.

Frank is very closed off about his personal life, going to great lengths to keep his relationships (the few there are) secret even from his family. After Kelly’s actions in the pilot episode, it isn’t hard to see why.