Patrick Galen Dempsey (born January 13, 1966) is an American actor and race car driver. He is best known for his role as neurosurgeon Derek "McDreamy" Shepherd in Grey's Anatomy. He had early success as an actor, starring in a number of films in the 1980s, including Can't Buy Me Love (1987) and Loverboy (1989).

In the 1990s, he mostly appeared in smaller roles in film, such as Outbreak (1995) and television. Dempsey was also in Scream 3 (2000) where he played the role of Detective Mark Kincaid.

He was successful in landing a lead role in Sweet Home Alabama (2002), a surprise box office hit. He has since starred in other films, including Brother Bear 2 (2006), Enchanted (2007), Made of Honor (2008), Valentine's Day (2010), Flypaper (2011), Freedom Writers (2007), Transformers: Dark of the Moon (2011), and Bridget Jones's Baby (2016).

Dempsey, who maintains a sports car and vintage car collection, also enjoys auto racing in his spare time. He has competed in pro-am events such as the 24 Hours of Le Mans, Rolex 24 at Daytona sports car race, and Ensenada SCORE Baja 1000 off-road race. Prior to the 2013 24 Hours of Le Mans, Dempsey declared that he would "walk away" from acting if he could and dedicate himself full-time to motorsports.