black leaves, warm to the touch

I have a major problem with one of my inherited plants.

Some of the leaves have turned black, they are wet and look like they've decomposed. They are warm to the touch, even through gardening gloves. On the same shrub I have a massive blackfly problem. I did also have a mystery bug...I felt rather silly when I pruned the "pest" out and then found out it was ladybug pupa...doh!

So...any ideas on the black leaves? I'm hoping there are some surviving ladybugs that will help me with the blackfly. They invaded my elderberry last yr so at least they're giving that a rest

I'm all for bio-diversity so I'd really like to leave the blackfly to the ladybugs if at all possible...but the black leaves are worrying. Please help :confused:

 

I think we definitly need a picture of this.

Never heard of leaves being warm to the touch.

What kind of plant is it?

 

I'll fish the leaves out of the green bin and try get a pic on here. Not sure on the plant, I have a feeling its supposed to be a tree but has been cut into shrub form if that makes any sense