Reload pickled objects into dict - assigned to variable name from file name
Here's a couple pieces of style advice, sourced from Python's style guide (PEP0008).

Keyword arguments shouldn't have space on either side of the equals sign:

def get_saved(directory='audio/', extension='en'):


Good that you're including a docstring, but one line docstrings should be on one line.

"""Get list of files, add them to a queue and return the queue."""


Also there may be a reason, but why not use the os module's os.path.join function instead of concatenation when making paths? It checks the OS you're on to ensure it's using the right syntax. It's generally a safer way than concatenation.

return glob.glob(os.path.join(directory, '*.' + extension))