Name those Plants: Edible Red Smooth Berries and Mystery Tentacles

While running the Glover-Archbold Trail in DC I came across two interesting specimens. One I've managed to name, the other continues to elude. First, the named one. Check out this tasty looking bush:

My ID: Hobblebush (Viburnum lantanoides = V. alnifolium):

Height to 10 ft. Leaves 4 - 8 in; toothed; brown-velvety, as are the buds and twigs. Buds naked (without protective scales). Flower clusters white (May - June). Fruits ovoid, at first red, then darker. A shrub commonly seen in wet areas or along streams ...

As you can tell from the above photos, the leaves are toothed, and while most of the berries are red, some are much darker. The samples I found grew relatively close to a stream, so all that checks out. The pictures that accompany the above description also appear to match. And the berries are edible, though one source lists them as possess[ing] a slightly bitter, spicy flavor. Yum.

One common rule, is to avoid red smooth berries because they are often poisonous. And of course, Hobblebush is an exception to this rule.

As for the one I can't name, check out this beauty:

The plant has red stems, leaves with red veins and friggin tentacles surrounding the soon-to-bust-out flower. How can I not find this guy on the web? If you know its name, please share in the comments.

One thing I've learned about plant identification is how the right life stage can make all the difference. Trying to identify raspberries before they have become tasty fruit was super tricky. But once the fruit was fully visible, it was trivial. So I'm thinking I'll make it a point to pass the above mystery plant over the next couple weeks and see what it turns into.