[1] His notable film appearances include WarGames (1983), Twins (1988), Dances with Wolves (1990), My Cousin Vinny (1992), Money for Nothing (1993), Devil in a Blue Dress (1995), Cutthroat Island (also 1995), The Sweet Hereafter (1997), Mouse Hunt (also 1997), The Mask of Zorro (1998), Entrapment (1999) and Mystery, Alaska (also 1999), Being Julia (2004), Blindness (2008), and Barney's Version (2010).

[3] His Canadian mother, Clarice Chaykin (née Bloomfield, 1921–2012),[4] was born in Winnipeg, Manitoba, but raised in Montreal, Quebec, since the age of three.

[7] After performing uninvited at an underground theatre festival in Toronto, Ontario, he was encouraged by artistic director Ken Gass to relocate there.

The New York Times reported Chaykin's "undisguised delight" at starring in the promotion for The Golden Spiders: "There's an extraordinary billboard up on Sunset Boulevard right now, with a humongous photograph of my face.

[citation needed] Two of Chaykin's early motion picture roles brought him public recognition: computer programmer Jim Sting in WarGames and prosecution witness Sam Tipton in My Cousin Vinny.

In 1990, he had a small but pivotal role in the film Dances with Wolves, portraying Major Fambrough, an Army fort commander who kills himself as a result of becoming insane.

In 2006, Chaykin appeared in an episode of the Ken Finkleman miniseries At the Hotel and received a Gemini Award for best performance by an actor in a guest role.

[citation needed] Chaykin starred as Sam Blecher, the owner of a family-run driving school in Winnipeg, in the first two seasons (2008–2010) of the Canadian comedy-drama television series Less Than Kind.

[10] "Sam is an out-of-control, good-hearted, big-hearted person who just can't quite get it right with his family," Chaykin told Q radio interviewer Jian Ghomeshi in April 2010.

[1] Writing for the Toronto International Film Festival, Brian D. Johnson summarized Chaykin's screen persona as "[bringing] an unnerving edge to whatever character he plays, a disturbing sense of dissociation.