The idea behind Inconstant Companions (which I have stuck under Big Finish even though it applies to more than that – e.g. Sally Sparrow) is to celebrate the one-off (so far) performances of those that bring various adventures to life or add tremendous depth due to the sheer quality of the performance and/or the writing.
This will dip into TV but mostly stay in the Big Finish range.
The rules (which I shall ignore) are:
- Only appears once (e.g. Liv Chenka); or
- Appears more than once but not as a travelling companion (e.g. DI Menzies); or
- Travels in the TARDIS but only within one story.