Ambitious on every level, but careful to never let spectacle overwhelm character. Doesn't labour scientific points and instead allows them to be driven, created even, by emotion, tying the universes together in a ball that's grand and vast yet tender and intimate.
Basically I fucking loved it and I was absolutely not expecting to.
Engagingly generous about where it expects your sympathies to lie; there are a remarkable number of characters who feel well shaded. Michael J. Willett is a soulful centre, but Sasha Pieterse might be more surprising in how quickly and deftly she undermines the character stereotype, even before the script does. Never outrageously funny, but greatly affectionate, and finds the thin line where it can employ both stereotype and subversion of it without feeling duplicitous or confused.