Lindsay Lohan celebrated her newfound freedom with a death-defying photo shoot  last week ... in the middle of an L.A. street ... replete with bloody knives and boob grabs.


It's her first photo shoot since the actress got out of house arrest two weeks ago -- taken in the middle of the night inside the famous 2nd Street tunnel in Downtown L.A.

If you're wondering who the dudes are ... it's Lindsay's photog BFF Tyler Shields and Virgin Mobile "Sparah"-half Spencer Falls ... who Lindsay was reportedly dating.

For the record -- Lindsay is NOT dating Spencer. But based on the pics, she's still a real handful.