There are lots of gaps in the series when multiple stories happen simulataneously, and not all the questions were answered in the finale of BSG. This goes some way to explaining at least some of these, and director and star Edward James Olmos manages to weave established footage with newly shot scenes in an elaborate web which gives an entirely different look on the whole series you think you know.
Star of this is Quantum Leap‘s Dean Stockwell playing, as ever Cylon John Cavil, in particular two different versions, one who singularly plotted and wants the complete destruction of humanity and another who – perhaps – sees the error of his ways. His performance is fabulous, subtley changing very little between the various Cavils but enough to allow us to see a shift, a shift which would eventually spread to the whole Cylon race.
Joining him it seems is the whole cast from the entire series, but this isn’t the case. Clever editing, CGI and splicing allows Olmos to slot in old scenes in the style of DS9’s Trials and Tribbleations with new shots and it’s a clever conceit which gives us a different angle to things we already knew and also allows us to see scenes we;ve only heard of in the past, like, for instance, the “mysterious stranger” who saved Ellen Tigh on Caprica.
The cast who do return slip perfectly back into their roles effortlessly and it’s a little bittersweet knowing that now this series has ended there’s no returning to these characters.
If I was to criticise it at all I’d suggest The Plan is a little elitist. You have to be a serious Galactican to get all the references, nods and continuity, but if you have followed the series completely and know what’s going on, this is a great extra and “joining the dots” which will have you salivating for more.