Pace's first role on the big screen was in 2003, playing the real-life trans woman Calpernia Addams in the movie Soldier's Girl, which described her relationship with the late Barry Winchell. Pace is also known for his roles as Roy Walker, Ned the Piemaker, Rep. Fernando Wood, and most recently, the Elvenking Thranduil and Ronan the Accuser.
- Soldier's Girl (2003) as Calpernia Addams
- Wonderfalls (2004) as Aaron Tyler
- The Good Shepherd (2006) as Richard Hayes
- Pushing Daisies (2007 — 2009) as Ned
- Miss Pettigrew Lives for a Day (2008) as Michael Pardew
- A Single Man (2009) as Grant
- When in Rome (2010) as Brady Sacks
- Marmaduke (2010) as Phil Winslow
- The Twilight Saga: Breaking Dawn — Part 2 (2012) as Garrett
- Lincoln (2012) as Fernando Wood
- The Hobbit trilogy (2012 — 2014) as Thranduil:
- Halt and Catch Fire (2014 — 2017) as Joe MacMillan
- Marvel Cinematic Universe (2014, 2019) as Ronan the Accuser:
- The Book of Henry (2017) as David Daniels
- Foundation (2021) (2021) as Brother Day
- Angrish: Roy's freak-out in the hospital in The Fall and scream-crying in the finale of Soldier's Girl were fueled by Pace's actual frustration and anger. Both scenes took all day to shoot, and Pace was fed up with all the fragmented takes they kept on remaking.
- Awesome, Dear Boy: Had no interest in doing TV until he saw the script for Pushing Daisies and "knew it was going to be great."
- Badass Baritone: Lee has a pretty deep voice, and this comes in handy when playing characters like Thranduil and Ronan the Accuser.
- Big Ol' Eyebrows: His most distinguishing quality.
- Creator Backlash: Claims he gave himself "a hard time" overdoing Marmaduke until numerous children came up to him and said they watched it over and over again.
- Dyeing for Your Art: To play a trans woman in Soldier's Girl, he lost twenty-five pounds.
- Fake Brit: In Miss Pettigrew Lives for a Day and Ceremony. Although The Hobbit isn't exactly set in England, he affects The Queen's Latin. Many assumed he actually was English for a while, if this interview is anything to go by.
- Method Acting: One of the best examples—his character Roy Walker in The Fall was bedridden and possibly paralyzed. He pretended to be a paraplegic and answered to the name "Roy" for the first 12 weeks of filming so his six-year-old fellow costar Catinca Untaru would act believably. Almost everyone on set thought he had lost the use of his legs in an accident, which the director encouraged. A lot of people were ticked when they found out the truth. A make-up artist apparently fainted with shock when she saw him standing up.
- Playing Gertrude:
- Two years younger than Orlando Bloom despite playing his father. Of course, Elves are immortal and eternally youthful, so it's not quite glaring.
- He was also roughly twelve years younger than Fernando Wood is supposed to be when Lincoln takes place.