Morena Baccarin & Ben McKenzie This Relationship Is Working

10/23/2015 1:41 PM PDT

Morena Baccarin and Benjamin McKenzie ... This Relationship Is Working

With nothing left to hide ... Morena Baccarin and Benjamin McKenzie are getting kinda touchy on the NYC set of "Gotham."

Even when cameras weren't rolling Thursday, Ben slipped in a little PDA with his baby mama.

Morena was wearing a baggy coat and scarf as they waited to shoot a scene ... so it doesn't look like they're working the pregnancy into a "Gotham" plotline.

As we've reported ... the co-stars plan to get married in the future ... once she can wrap up her nasty divorce.