Lindsay Lohan did a late-night photo shoot with photog pal Tyler Shields in downtown LA Tuesday, and the pics are out!

And that's not all that's out ... Lindsay's breasts make a pretty prominent appearance in the shoot ... and they're getting manhandled!

The pics -- all in our gallery below -- show Lindsay holding a bloody knife, in bed, dancing ... there are lots of top hats. It's all very Panic! At The Disco, in our humble opinion.

Shields included some comments with the pics:

    "In matters of love sometimes you have to be willing to get your hands dirty. ... Lindsay Lohan Spencer Falls and I had way to much fun on this one! ... A little romance never hurt anyone until it ended."