If Firefly counts, Babylon 5's attempted successor Crusade counts more so. It supposedly had 5 years planned, and was also cruelly cancelled after a lot of network notes and drama including airing some episodes out-of-order/at weird times.
JMS at least didn't try to cram the remaining plot into a single film. Some of the plot is out there as unfilmed scripts and some made its way into book series, and most of it we may just never know at this point because WB doesn't care about Babylon 5.
JMS at least didn't try to cram the remaining plot into a single film. Some of the plot is out there as unfilmed scripts and some made its way into book series, and most of it we may just never know at this point because WB doesn't care about Babylon 5.