Metwally was born in Queens, New York to an Egyptian father and a Dutch mother, and moved with the family to Orange County, California at age three where he was raised. Metwally gained a BA in History from the University of California, Berkeley, and while acting around the Bay area gained an Master of Fine Arts in Acting from the American Conservatory Theater, San Francisco.
Metwally's film roles include Gavin Hood's Rendition and Steven Spielberg's Munich, The City of Your Final Destination, released in 2010 (filmed 2006-07), and Amsterdam. He received the 2008 Chopard Trophy for his work in Rendition, presented at the Cannes Film Festival. Metwally will also be seen in the forthcoming film Miral from director Julian Schnabel.
Metwally moved to New York in January 2000 and began working there, appearing in 2005 as "Aram" in Beast on the Moon directed by Larry Moss, and receiving a 2004 Tony Award nomination for his work in Sixteen Wounded. He has worked with the New York Arab-American Comedy Festival, first as an actor and then as a director. He has also appeared at theaters around the country, including Steppenwolf, The Public, the Long Wharf, Berkeley Rep, and many others.
Metwally's television credits include Virtuality, Fringe, The Unit, and Grey's Anatomy.
Metwally resides in California.