Keanu Reeves and Alex Winter travel through time to save reality and redeem the honor of Generation X.

Which isn’t to say that all heinousness has been banished. That was the promised outcome of “Bill & Ted’s Bogus Journey” (1991) — the second of the earlier “Bill & Ted” movies — which ended on a high note of rock ’n’ roll utopianism. The universe was united in song and the future was secure. Somehow, it hasn’t worked out that way, either on a personal or a cosmic level.

Was it enough? Of course not. Bill and Ted belong to a generation so closely identified with failure as to be routinely erased from the record. The new movie, directed by Dean Parisot, is an amiable, sloppy attempt to reassert the value of friendliness and crack a few jokes along the way. The Wyld Stallyns bassist, Death (Bill Sadler), supplies a lot of those, as does a neurotic killer robot named Dennis (Anthony Carrigan).