Time Rifters is a superheroic game using (to date anyway) 5th Edition Revised Hero Rules.

Each episode of Time Rifters is a "one-off" -- the GM(s) and players consent to come together to tell a story with a definite beginning, middle, and ending. After the end and denoument each participant gets to decide if they'd like to opt in for the next episode. This means that the story as a whole is a collaborative effort among many Game Masters and Players, all taking turns moving groups of characters through time to right wrongs or wreak havoc, whichever the case may be.

So you can think of the many episodes of Time Rifters as an anthology of sorts and be right on the mark. The GMs may change, players and characters may rotate in and out -- but the idea is always to get together to tell one story, and have as much fun as you can stand while doing it.