Something's browsing! Do you have any deer or boars in your neighborhood? Rabbits or hares are also possible, but their damage is usually from the bottom up, rather than the top down.

I have seen a doe in my garden once. I did think it could be a deer but there are no foot prints anywhere around the plants. Also 1 plant has been almost completely deleaved and the one next to it which is more accessible is almost untouched only few buds missing.

Deer look like the most obvious culprits. I came across one eating a friend's roses and I don't know who jumped highest! Perhaps yours was disturbed before it ate the other one.

We used to keep goats and they just loved the chance to escape into the garden, rose bushes being the No. 1 favourite. Deer are just the same. Your roses are being grazed but I would have expected deer to take the twiggy stuff as well, not just cherry pick the more tender leaves.

My first thought was a deer too but its happening in the front garden too. Could it be some sort of a bird or an insect. As I said, no foot prints anywhere around the roses and literally just the leaves and buds ripped off, stems left behind.

Very unlikely to be a bird or insect completely removing leaves

I have a very large healthy groundhog that is fattening up for the winter on my sweet potatoe vines and the condition of the vines looks very similar. I have even seen the g-hog standing upright to eat the leaves hanging from 4 ft plant stands and it even knocked a gazing ball off its pedestal so it could climb up the pedistal to get to the top of a 5ft plant stand. They have amazing agility and are fun to watch and he is welcome to whatever is in my garden that will get him or her through the winter. If it's an annual it saved me the trouble of removing it. If it's a perennial, it cut the plant back for me...job done. I don't think you have groundhogs aka whistlepigs in the U.K. Now that it is October it will soon be going into hibernation in its burrow dug for that purpose.

Well, whatever it was has now moved on to my japanese acer.

Ouch! That will take longer to recover. Have you tried hanging bars of your favorite soap up in the nooks of your garden. Supposedly, they smell it, and then think that you are there, watching.

The acer isnt too bad as the leaves are just starting to turn with autumn and fall. I was more worried about my David Austin roses as this have never happened before

I would have to know what's doing it. Do you have a good view from upstairs? I'd be inclined to watch and wait during the night and try to see what it is.