How would life be different if there were two of you? If you had another person walking around who looked the same and went through the same experiences as you do? How would your identity change if you were identical to someone else? If your most important relationship was built with someone who had the same DNA and upbringing as you? For those born with an identical twin (which occurs in about 4 of every 1,000 births), this is the reality. And though every identical twin is born with their perfect match, each set of twins experiences twinship uniquely. That's the topic that's explored in a new documentary, Two of a Kind, which will air on the Documentary Channel on Nov. 30 at 9 p.m. (Another version will also run on CBC’s The Nature of Things on Nov. 27 at 8 p.m.) The filmmaker behind the documentary, Leora Eisen, has spent her life with an identical twin sister, Linda Lewis (pictured above), and was always asked what it was like to be a twin. It’s a complex relationship that has left many non-twins questioning: What would it be like? While there can be an extra-strong kinship (or twinship, if you will) formed by sharing so much with another person, there can also be a loss of identity or individuality, and each set of twins works out that compromise in a surprisingly different way. Leora was inspired to make a film about the relationship that had impacted her life so dramatically. Through the documentary she looked at twins who are inseparable, twins who are at odds, twins who are utterly dependent on each other and twins who couldn't be more independent. Twins go through much of life together and it's beyond fascinating to see how their shared experience can either draw them closer in their bond together or exacerbate their differences. For Leora Eisen, there's only one way to describe her twinship: soul mates. Unfortunately, for twins like Leora and Linda who are used to sharing everything, life’s disasters become even more difficult when they single out one half of the pair. When Linda was diagnosed with cancer, Leora was stricken not just with fear for her sister's life but guilt for not suffering herself. If you’ve ever wondered what it’s like to be one of two, this sometimes cheeky, sometimes heartbreaking doc will offer a rare glimpse of life as a double. Unlike a twin, there really is nothing else like it.