After graduation at
Mountview Academy of Theatre Arts in England, Dallas joined the
Royal Shakespeare Company, and then took part with the
Royal National Theatre,
English National Opera, the New Shakespeare Company, and the
Young Vic. Returning to the United States, he was cast as
Fandral in
Thor after Irish actor
Stuart Townsend withdrew from the role days before filming was to begin. As he was a virtually unknown actor when cast, there was some speculation that Dallas was selected because there simply was not enough time to find a bigger-name replacement. To prepare for the role, Dallas viewed
Errol Flynn as an inspiration (
Stan Lee, in 1965, created the character based on Flynn), and watched many of his films. He commented, "I tried to bring out that little bit of Flynn-ness in it. Flynn had a lot of that boyish charm and Fandral's got all that in him." Dallas did not reprise his role in the
sequel to Thor.
Zachary Levi replaced him in the subsequent two films. In 2011, he began starring in the
ABC series
Once Upon a Time as Prince Charming. After six seasons, Dallas did not appear in season 7 in 2017. He returned for its series finale the following year. From 2018 to 2023, he starred as Ben Stone, in the hit
NBC mystery/drama series
Manifest, which premiered on September 24, 2018. ==Personal life==