Josh Kriegman and Elyse Steinberg, Directors of 'Weiner'

When documentary filmmakers Josh Kriegman and Elyse Steinberg starting filming former Democratic congressman Anthony Weiner in 2013, the plan was to capture what could have been an amazing comeback story. Weiner had resigned from Congress in 2011 over a sexting scandal. Yet when he launched a run for mayor of New York City two years later, polls were moving in his favor.

The new documentary Weiner captures the high-energy politician working his campaign magic and includes glimpses of his wife, Huma Abedin, a long-time aide to Hillary Clinton, at home and at work. The camera continues to roll when news of a second sexting scandal breaks.

To the bitter end of his crumbling campaign, Weiner never asked Steinberg and Kriegman to stop filming. So they didn't. It was a strange turn of events, especially for Kriegman, who had once worked at Weiner's chief of staff.

Steinberg and Kriegman tell us why they opted to keep filming even once Weiner's campaign tanked, and why they think Weiner didn't kick them out.

Weiner is in theaters now and will air on Showtime later this fall.