1. Special Agent John Doggett, The X-Files (2000-2002)
Following after a departing lead character is never an easy task for any actor, especially if said character is as beloved as Fox Mulder was. But the producers could not have found a better successor than Patrick as Special Agent John Doggett. With his no-nonsense attitude and that stare that could go through people, Doggett was tough enough to handle everything the X-Files Division could throw at him - which was a lot. In just two years on the show, he found out two of his old friends were super soldiers (one of which tried to kill him multiple times), got amnesia, died, and came back to life. That's intense.
What made Doggett one of the best heroes ever to have graced the science-fiction genre, though, was how complex he was. As enjoyable as it was when he was saving Scully or helping Mulder, he was just as good when viewers got to see his more vulnerable side, and Patrick played that just as well. Two of the best episodes from The X-Files' final years, Season 8's "Via Negativa" and Season 9's "Release," are great episodes because of the amazing, heartbreaking performances he gave in them. Even when the episodes were lacking, he was always good.
Doggett might only have been with the X-Files for two years, but by the end, he felt like someone who'd been there a lot longer. It's unfortunate that the cancellation of The X-Files meant that his character didn't get to be explored any further, because there was still plenty of life left in him - and to this day, a decade later, I still wonder where he might be. That's the mark of a truly great character.