It would need a big tub but fatsia japonica could fit the bill otherwise I'd look at grisellinia littoralis, eleagnus ebingii or Prunus laurocarocis ...but all would need hefty ol' tubs

Or even a bamboo - my Phyllostachis aurea looks wonderful all year. That would grow in a (large) pot.

Agree with Spritzhenry - I came on to suggest Phyllostachys nigra, but which you choose is down to you.

Thank you all - I had thought of bamboo but wasn't sure. I'll check out all of your suggestions, thank you!

You'll need a big pot for bamboo - preferably a minimum of 18 inches deep and 12/16 inches wide. A larger pot also helps prevent it getting blown over, so long as its not dried out.