Ephesos Terrace House 2. That's the retiarius with his spear and net on the right and the secutor with his shield and funny-looking helmet on the left. Apparently the secutor was supposed to look like a fish, with the retiarius as the fisherman. Kind of a sick metaphor for a bloodsport, but that was the Romans for you, they liked their cruelty dressed up in pastoral sentimentality.
Thanks to Sinan Ilhan for the behind-the-scenes tour that let me get this close!