But, it appears, not everyone was initially sold on casting her as super spy Sydney Bristow.
Series creator J.J. Abrams revealed that some TV honchos were apprehensive about Garner in the lead role. One exec's particular concern: Was Garner "hot enough"?
"I wrote Alias thinking about her," Abrams – who had worked with Garner on his other TV show, Felicity – said Friday during a conversation with Chris Rock at the Tribeca Film Festival in downtown Manhattan, as part of the fest's ongoing Tribeca Talks series.
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"I finished it, she came in, was amazing," he recalled of Garner's audition. "And I remember someone at the network was like, 'I don't know, is she hot enough?' "
Garner went on to snag the role, playing the stealth double agent for five seasons until 2006, a move that helped boost her leap to the big screen.
"They're always second-guessing, everyone's always afraid at networks," Abrams said of the initial hesitation.
Of course – with a rich career filled with diverse projects, including the recently released Miracles from Heaven – Garner, now 43, has since proven those early skeptics wrong. Then again, Abrams never doubted that from the very start, he had the perfect star.
"Jen was so great, and she did everything," he said. "And it was incredible doing the pilot – I remember watching her kind of find this strength in herself. It was just so cool to see, and she just did a spectacular job."