Inexpensive pre-theater dinner near Calderwood in So End?
If you are willing to walk a little bit in any direction, there are a lot of good options.
Toward Back Bay, Salty Pig, Giacomo's on Columbus next to Anchovies.
Franklin Cafe is close, good, perhaps a little bit more expensive but less than other places in the S. End.
The Gallows or Myers and Chang on Washington.
Orinoco for Venezuelan, El Triunfo for cheap Mexican, Vejigantes for Puerto Rican.
The Buttery also serves inexpensive dinners.