This sounds like the There and Back, but you could be watching a simple lockstep.

I think it could be Cuban Break.

SOunds like a lockstep to me.

It could be the Three chac chas:

Lady's steps: Right foot back on count 2, left foot in place on 3, lock steps forward on 4 & 1, 2 & 3, 4 & 1, then left foot forward on 2 and in place on 3, then lock steps back like the forward steps.

Guy's steps: Just the opposite, of course. Left foot forward on count 2, right foot in place on 3, lock steps backward similar to the lady's except in backward direction.

It's a piece of cake for you and you will love the steps. You can do whatever makes you feel comfortable with your hand movements.

I don't think he means Three Cha Chas, because you change feet for that step. I don't know the name for the step you're referring to, and I just call it a Continuous Lock Step, personally.