It'll be deemed that there's no significant difference between them, they'll both be ranked dead last, probably in episodic order, (irritatingly, cos I'm with you, my vote's for Love & Monsters,) and the process will continue.
What I did consider doing, is I might withhold my vote on a tiebreak round, so if the results are revealed and a deciding vote is necessary, I can cast it and move on. If that sounds too tyrannical (it shouldn't, because it means I wouldn't be participating at all in the vast majority of tiebreakers) I might do the opposite, and vote at first but revoke it if there's an unbreakable tie. I might do that anyway, in this case, seeing as the first option's off the table now I've voted.
Another option, and it's probably fairer because it doesn't leave me with a casting vote, would be to tally up the performances in all previous rounds. Two stalemates in a row, overall performance comes into play. Wouldn't work for a round one tie, but it feels more democratic. So I'll do that, if necessary and when possible.