That's Dr. Kev in the bottom left hand corner. Dr. Alex is dressed as Lando on the bottom right.
WHAT HAVE YOU DONE WITH OUR BELOVED SHEILA?
Patients have been wondering, often loudly, where our dental assistant Sheila has been for the past six months. We were initially suspicious when she told us that she'd had a vision of Alec Guiness in a snow storm telling her to go meet a puppet on another planet, but we went with it. Turns out, we were right to both be suspicious and be supportive. She's back, and now she's a full-fledged Jedi Knight. She's picking up rocks with the force, tricking local policemen into letting us board spaceships, and she's trying to act like that's not a lightsaber in her purse. We know better. Those kanji characters on the poster roughly translate to "LOOK OUT CHATHAM COUNTY THIS JEDI KNIGHT LIKES TO HELP CHILDREN WITH THEIR TEETH AND HEY WHO IS THAT WELL I GUESS IT IS LUKE SKYWALKER."