UPDATED: See below

The final hours of a legislative session are often littered with strange alliances and stranger votes. But it's rare to see a complete and sudden flip on one of the hottest topics of the year.  

Rep. Susi Hamilton, D-New Hanover, signed a letter last week asking Gov. Bev Perdue to veto Senate Bill 820, the fracking bill. Monday night, she voted with the GOP majority to override the very veto she asked for.

Hamilton has consistently voted against proposals to explore fracking. In fact, she was recently recognized by the NC League of Conservation Voters as a "2012 Rising Star." 

Without Hamilton's vote, the veto would have been sustained. 

The switch left Will Morgan with the NC Sierra Club shaking his head. 

"It's disappointing that someone who was recognized for her environmental ethics traded her vote on the most important environmental vote of the session," Morgan said of Hamilton. 

Asked what he believes Hamilton traded her vote for, Morgan wouldn't say. "A week ago she asked the governor to veto the bill. Something happened to change her mind. People can figure it out." 

That "something" may have been a $60 million film tax credit that was slipped into a bill intended to clean up typos and technical errors in other bills. 

The proposal had gotten little traction before tonight. But Senate Bill 847, the Technical Corrections bill, was rushed into House Finance late Monday night, where the tax credit was inserted, shortly before the fracking veto override vote. 

The film tax credit is scheduled to expire at the end of 2013. The new proposal would extend it through the 2014 calendar year. A new production of Captain America is said to be considering a location in Hamilton's district, but work would likely spill over into 2014. 

When Senate Bill 847 passed the House late Monday night, a jubilant Hamilton high-fived Rep. Danny McComas, a Republican from New Hanover who championed the tax credit extension.

WRAL tried to interview Rep. Hamilton, but she was not available to talk with us tonight. 

UPDATE: By email, Rep. Hamilton said she did not intend to ask for a veto on fracking: 

The letter I agreed to regarding a veto over ride was S382, an environmentally unfriendly bill with an additional clause requiring cities to provide municipal services in the unincorporated areas of the county. I did not realize it was being included in the same message for S820. I did not review the letter before it was released. I had not discussed my position on the bill with Rep. Harrison. I'm sure she sent the letter on good faith. It was just lack of communication, which can happen when we are moving bills at lightening speed.