It's not possible in this way that you're thinking. At least, not yet (see issue 40).
But, depending on your script usage, you may connect them "the hard way" or even better, use only one script. The script on the master spreadsheet can open the other spreadsheet files and do its job "remotely". It's not required that script to be hosted on a spreadsheet to interact with it (read/write on it). You only need a script hosted on the spreadsheet if you're going to use spreadsheet events triggers i.e. on-open, on-edit and on-form-submit.
Maybe you can develop a nice UI for the script on the master sheet and publish it as service. Then only have a link on the copies to access the same UI on a different browser tab. Adding parameters to the link the script UI can even adapt to the particular spreadsheet that is "triggering" it.
Well, that's all I can imagine now. But, unfortunately, there's some use cases that just don't fit this nice "workarounds". For those, one can only star issue 40 (to kind of vote and keep track of updates) and hope it's developed soon.