- Cast Incest: Early in the show's run, onscreen mother and son Joely Richardson (Julia) and John Hensley (Matt) were dating in real life (regardless of their 12-year age difference).
- Dawson Casting: Really obvious on Matt. It gets a little creepy as the actor playing Matt was dating the actress playing his mom (like Matt didn't have enough issues).
- Fake American:
- Julian McMahon (who is from Australia) and Joely Richardson (from England) as Americans. In general, Richardson's American accent is much more accurate than McMahon's (except when she says the word "family"). Also, Rhona Mitra who plays Kit McGraw is revealed to be American, although Mitra is English.
- Averted and then played straight with Kit McGraw. Rhona Mitra used her real British accent in playing the character, but in her last appearance, the character was revealed to be faking it, and used an American accent.
- Also Montrealer Jessalyn Gilsig.
- Fake Brit: Inverted with Jude Watson and Kit McGraw. They both play as an American character who are faking their British accent for one reason or another, but both Phillip Rhys and Rhona Mitra were born in London, so the accent they're "faking" in the show is actually their authentic accent in real life.
- Fake Nationality: American Maggie Stiff portrays Israeli bombing victim Rachel Ben Natan.
- Technology Marches On: In a third-season episode (aired in 2005) Troy and McNamara attempt a full face transplant, which they admit while theoretically possible, has never been done successfully. Sure enough, in the episode the procedure ultimately fails as the recipient's body rejects the transplant. The world's first successful full face transplant was accomplished in 2010 in Spain.
- The Other Darrin: Teddy Rowe is played by Katee Sackhoff, then Rose McGowan.
- Real-Life Relative: Julia's mother is actually played by the actress's real-life mother Vanessa Redgrave.
Trivia / Nip/Tuck