It's Always Sunny in Philadelphia - Season 1 Episode 4 -

After discovering that he might have cancer, Mac and Dennis attempt to find a woman who will sleep with Charlie. In the midst of their search, Mac falls in love with a transsexual he meets at the bar named Carmen. Overwhelmed by the extra workload that she had to take on since Charlie has taken a leave of absence, Dee tries to get Dennis to hire a recently out of work actress friend to help out.