Martha meets a different kind of Companion, Part 1
Disclaimer: The BBC owns 'Doctor Who' and Joss owns 'Firefly', not me.
"And this is Inara Serra."
One look at this woman stops her dead in her tracks. When she glances at the Doctor, she sees he's had a similar reaction to this absolutely stunning woman.
He never looks at her THAT way. He sees something in Inara, something Martha herself doesn't have. When Inara explains her job as a Companion to Martha, she begins to formulate a plan.
During their time on Serenity, The Doctor spent most of his time attempting to fix the TARDIS, which left Martha free to do as she pleased. That suited her just fine, as right now she had an appointment with Miss Inara Serra.