[7] Cast by Jennifer Starr, he became the first male in the world to secure a six-figure deal to model exclusively for Calvin Klein for a year, and the last to be personally contracted by the brand's eponymous designer.

[14] Fimmel began his acting career by appearing in the music videos for Janet Jackson's song "Someone to Call My Lover"[15] and "I'm Real" (original version) by Jennifer Lopez, both in 2001.

[26] The film is based on a real-life experiment on volunteers by Stanford University that was cut short after spinning out of control, with "guards" exhibiting sadistic behaviour and "prisoners" suffering depression.

[32] Fimmel played the lead in 2012's Harodim with Peter Fonda as a former intelligence officer trained in black ops tracking down the world's most wanted terrorist, who is compromised by his own chain of command.

[33] He co-starred with Billy Bob Thornton and Eva Longoria in the 2012 redneck Southern comedy flick The Baytown Outlaws, playing one of the three hapless Oodie brothers who bites off more than he can chew when he agrees to help a woman get her godson back from her deadbeat ex-husband.

[34] Fimmel was signed as the lead character for four seasons in the critically acclaimed drama television series Vikings, co-starring Alexander Ludwig, Katheryn Winnick, Gabriel Byrne, Gustaf Skarsgard, and Linus Roache.

[43][44] He was cast as a quirky hipster in the romantic comedy Maggie's Plan with Ethan Hawke, Greta Gerwig, Maya Rudolph, Bill Hader and Julianne Moore, and a loving but irresponsible father in Lean on Pete with Charlie Plummer and Steve Buscemi.

Set in the 1930s Dust Bowl, the story follows a teenage boy on his quest to beat out the FBI to capture a fugitive bank robber in order to claim a bounty and save the family farm.

[51][52] In 2020, Fimmel featured as a TV presenter in Here Are the Young Men, which was adapted from a novel about three Dublin high school graduates whose epic binge to mark the end of an era is blighted by catastrophe.

[58] In a review of his role as a killer-for-hire in the 2021 action-crime thriller Die in a Gunfight, Forbes states that Fimmel "steals every scene he’s in and has what could be the most compelling and morally tangled [character] arc of anyone in the entire story".

[60] He also appeared in indie drama Delia's Gone, co-starring Marisa Tomei, based on a short story about a black man with an intellectual disability who is accused of his sister's murder and embarks on a journey to clear his name and find out who's responsible.

[73] He was cast in Stan's satirical series Caught with Susan Sarandon, Sean Penn, Matthew Fox, Lincoln Younes, and real-life Channel 9 TV presenters Karl Stefanovic and Ally Langdon.

The storyline centres around four irreverent Australian soldiers mistaken for Americans in a war-torn country who realise that they can be social media famous when they produce a hostage video that goes viral.

[76] Fimmel was cast in the western film Rust, but production was temporarily suspended in New Mexico when a prop gun with a live bullet allegedly fired by co-star Alec Baldwin killed cinematographer Halyna Hutchins and led to involuntary manslaughter charges.