I want to get immersed in a series, really believe in the characters, and then have them mess with me. E.g. Friends + the 'what if' episode (Phoebe a businesswoman, Ross still married, Joey a successful actor etc etc). e.g. about 7 different Buffy eps (buffy never came, zander is twins, evil willow, Giles shapechanges, Faith and Buffy switch bodies, etc etc).
Do most series do this sort of thing?