Mystery Plant

I have identified a few mystery plants.
One I discovered was Garlic Mustard which is a highly invasive noxious weed.

The other I discovered is Solomons Seal Plume which is a native plant to Minnesota.

I have determined that this is a White Campion which is a non-native species to MN.

This plant however is giving me a run for my money.

I have no clue what it could be. I have gone through every photo on the minnesotawildflowers.com website. I have looked through most of the USDA plant database.  If i had some batteries i would take more pictures because the head are starting to open up a bit more. Hopefully ill find out what it is before i go insane. The plant is located over in the same area where the Columbine is. People on the wildlifegardeners.org forums think its either Angelica or Carrion Flower (Smilax H.). The Angelica seemed reasonable but this plant is lacking the leaves that Angelica would have. The Carrion Flower I don't agree with since this isn't acting like a vine, isn't woody enough and also lacks the leaves.

But I am not a Botonist so anyones guess is as good as any.

I have also found Wild Geranium in the area as well.