(written from a Production point of view)
Richard McGonagle (born 22 October 1946; age 73) is the actor who portrayed Ja'Dar in the Star Trek: The Next Generation fifth season episode "New Ground" in 1991. McGonagle filmed his scenes on Thursday 10 October 1991 on Paramount Stage 8 and 9. His costume from "New Ground" was sold off on the It's A Wrap! sale and auction on eBay. 
McGonagle appeared in the television movie Justin Case with fellow Star Trek actor Jennifer Edwards. Other television appearances include Quantum Leap with Scott Bakula and Dean Stockwell. He also lent his voice to the film Spirit: Stallion of the Cimarron, along with James Cromwell, Adam Paul, Matt Levin and Charles Napier, and also held an uncredited role in the 1987 pilot episode of 21 Jump Street as Mr. Weckerle. His film work includes the 1988 comedy 14 Going on 30 with Daphne Ashbrook and Judith Jones.
He was more recently seen in the fourth season finale of Boston Legal, the ABC drama series starring William Shatner and John Larroquette. McGonagle's episode, entitled "Patriot Acts," also guest-starred Jude Ciccolella and Henry Gibson. He was also the narrator for the 2009 movie (500) Days of Summer and provided the voice of Victor Sullivan in the games Uncharted: Drake's Fortune, Uncharted 2: Among Thieves, and Uncharted 3: Drake's Deception, opposite Nolan North.