On HBO's '70s sex industry drama The Deuce, which premieres Sunday, James Franco plays twin brothers Vincent and Frankie Martino. Most shows give viewers an easy way to tell identical twins apart if identity confusion isn't part of the twins' storyline, but The Deuce is committed to authenticity. That means since the Martinos are identical twins, they're really identical: the same haircut, the same mustache, the same ever-present cigarette.

But here's the thing: it seems like it would be difficult to tell them apart, but it's not. Their personalities are so different and Franco's acting is so precise that if you're paying attention you'll never mix them up onscreen. Vincent is the responsible one, and Franco plays him with a weariness that manifests in a certain clenched quality to his face. When he smiles, it's much tighter than careless Frankie's big grin. Frankie is the jokester, the hustler. Plus, the pilot gives you a freebie by putting a bandage on Vincent's head after he gets beat up by some goons who think he's his debt-ridden brother.

For more tips on how to tell the two Martins apart, TV Guide went straight toT he Deuce co-creator David Simon and actors Gbenga Akinnagbe, Chris Coy and Chris Bauer. Check out what they had to say in the video above.

James Franco and James Franco,<em> The Deuce</em>James Franco and James Franco, The Deuce

The Deuce premieres Sunday, Sept. 10 at 9/8c on HBO.