"We shot [Twinless] before Saturday Night, and that was not my mustache — that was a fake one," O'Brien said of the Saturday Night Live biopic. "They made me wear a fake one for Aykroyd because ...

O'Brien's Twinless mustache, however, was 100 percent real. "This was mine," he explained. When asked if he preferred sporting his own facial hair rather than a fake mustache, O'Brien admitted ...