[1][2] After early roles in Howard Hawks' El Dorado (1966), Robert Altman's Countdown (1967) and Francis Ford Coppola's The Rain People (1969), Caan gained acclaim for his portrayal of Brian Piccolo in the 1971 television movie Brian's Song, for which he received a Primetime Emmy Award for Outstanding Lead Actor in a Limited Series or Movie nomination.

He continued to receive significant roles in feature films such as Cinderella Liberty (1973), Rollerball (1975), A Bridge Too Far (1977), Comes a Horseman (1978), Chapter Two (1979) and Thief (1981).

After a five-year break from acting, he returned with roles in Gardens of Stone (1987), Misery (1990), Honeymoon in Vegas (1992), Eraser (1996), Mickey Blue Eyes (1999), The Yards (2000), City of Ghosts (2002), Elf (2003) and Get Smart (2008).

"[16] Caan began appearing off-Broadway in plays such as Arthur Schnitzler's La Ronde[17] before making his 1961 Broadway debut in Blood, Sweat and Stanley Poole.

[23] His first film was Irma la Douce (1963), in which he had an uncredited bit part as a U.S. soldier with a transistor radio more interested in a baseball game than the girl.

Watch him in his early movies and TV appearances, and he’s simply got “it”: he was handsome, virile-looking, and could act (New York trained, Broadway broken).

He had an uncredited spot on the spy sitcom Get Smart as a favor to star Don Adams, playing Rupert of Rathskeller in the episode "To Sire with Love".

[36] Caan won praise for his role as a brain-damaged football player in The Rain People (1969), directed by Francis Ford Coppola.

[38] None of these films, apart from El Dorado, was particularly successful at the box office, including Rabbit, Run (1970), based on the John Updike novel of the same name, in which Caan had the lead.

[49] He was in a road movie, Slither (1973), based on a script by W. D. Richter;[50] and a romantic comedy with Marsha Mason, Cinderella Liberty (1973), directed by Mark Rydell.

[51] He received good reviews for playing the title role in The Gambler (1974), based on a script by James Toback originally written for Robert De Niro, and directed by Karel Reisz.

[62] He had a change of pace when he went to France to make Another Man, Another Chance (1977) for director Claude Lelouch alongside Geneviève Bujold,[63] which Caan did for "peanuts"[64] and "loved" the experience.

[67] In 1978, Caan directed Hide in Plain Sight, a film about a father searching for his children, who were lost in the Witness Protection Program.

[69] During Caan's peak years of stardom, he rejected a series of starring roles that proved to be successes for other actors, in films including M*A*S*H, The French Connection, One Flew Over the Cuckoo's Nest, Close Encounters of the Third Kind, Kramer vs. Kramer ("it was such middle class bourgeois baloney"[70]), Apocalypse Now (because Coppola "mentioned something about 16 weeks in the Philippine jungles"[64]), Blade Runner, Love Story, and Superman ("I didn't want to wear the cape".[64]).

[70][71] In 1977, Caan rated several of his movies out of ten – The Godfather (10), Freebie and the Bean (4), Cinderella Liberty (8), The Gambler (8), Funny Lady (9), Rollerball (8), The Killer Elite (5), Harry and Walter Go to New York (0), Slither (4), A Bridge Too Far (7), and Another Man Another Chance (10).

[77] From 1982 to 1987, Caan suffered from depression over his sister's death from leukemia, a growing problem with cocaine, and what he described as "Hollywood burnout"[70] and did not act in any films.

"[80] Caan returned to acting in 1987, when Coppola cast him as an army platoon sergeant for the 3rd U.S. Infantry Regiment (The Old Guard) in Gardens of Stone, a movie that dealt with the effect of the Vietnam War on the United States homefront.

[83] Caan was planning to make an action film in Italy, but then heard Rob Reiner was looking for a leading man in his adaptation of Stephen King's Misery (1990).

[87] In 1996, he appeared in North Star, a Western; Bottle Rocket, the directorial debut of Wes Anderson;[88] Eraser, with Arnold Schwarzenegger;[89] and Bulletproof with Adam Sandler and Damon Wayans.

[93] Caan was in The Yards (2000) with Mark Wahlberg and director James Gray, Luckytown (2000) with Kirsten Dunst, and The Way of the Gun (2000) for Christopher McQuarrie.

[94] Caan starred in TV movies like Warden of Red Rock (2001) and A Glimpse of Hell (2001), and was in some thrillers: Viva Las Nowhere (2001), In the Shadows (2001), and Night at the Golden Eagle (2002).

He was in Lathe of Heaven with Lukas Haas (2002), City of Ghosts (2002) with Matt Dillon, Blood Crime (2002), The Incredible Mrs. Ritchie (2003), and Jericho Mansions (2003).

[95] Most of these films were not widely seen, but Dogville (2003) and Elf (2003), in which Caan had key supporting roles, were big successes on the art house and commercial circuit respectively.

[96][97] In 2003, Caan portrayed Jimmy the Con in the film This Thing of Ours, whose associate producer was Sonny Franzese, longtime mobster and underboss of the Colombo crime family.

[98] The same year, Caan played Will Ferrell's estranged book publisher father in the enormously successful family Christmas comedy Elf, and auditioned for, and won, the role of Montecito Hotel/Casino president "Big Ed" Deline in Las Vegas.

[106] Caan appeared in Henry's Crime (2010), Detachment (2011), Small Apartments (2012), That's My Boy (2012) with Adam Sandler, For the Love of Money (2012), and Blood Ties (2013).

In 2014, Caan appeared in the dramatic comedy Preggoland, playing a father who is disappointed with his daughter's lack of ambition, but who becomes overjoyed when she (falsely) announces that she is pregnant.

In a 1994 interview with Vanity Fair, Hollywood madam Heidi Fleiss claimed to be in a relationship with Caan during his marriage to Hajek in 1992, visiting him on the set of Flesh and Bone in Texas.

"[121] During production of The Godfather in 1971, Caan was known to hang out with Carmine Persico, also known as "The Snake",[122] a notorious mafioso and later head of the Colombo crime family.

[128] On July 6, 2022, Caan died at Ronald Reagan UCLA Medical Center in Los Angeles, at the age of 82, from a heart attack caused by coronary artery disease.