Version One:
[C]reate a team of four heroes, a.la the League of Extraordinary Gentlemen, only the catch is that each hero must be a character portrayed by the same actor.
Thus, the League of Extraordinary Patrick Stewarts:
1. Ahab, monomaniacal commander of the whaling ship Pequod;
2. Ebenezer Scrooge, newly-reformed uber-capitalist (and the group's financier);
3. Professor Charles Xavier, mutant telepath and educator; and of course
4. Jean-Luc Picard, starship captain.
One could also have the League of Extraordinary Sean Connerys:
1. Allan Quartermain;
2. Robin Hood (from the film Robin & Marian);
3. James Bond; and
4. Draco the dragon (from Dragonheart).
Finally, the League of Extraordinary Johnny Depps:
1. Jack Sparrow;
2. Ichabod Crane;
3. Willy Wonka; and
4. Dr. Hunter S. Thompson.
Then there's Version Two:
[C]reate a team of four to eight members, which comprise of sets of doubles as played by the same actor.
Here goes...
1a. Dr. Sam Beckett, time-traveler (Scott Bakula),
1b. Jonathan Archer, starship captain (Scott Bakula),
2a. Dennis/Denise Bryson, DEA agent (David Duchovny),
2b. Fox Mulder, FBI agent (David Duchovny),
3a. Ra's al Ghul (Liam Neeson),
3b. Qui-Gon Jinn (Liam Neeson),
4a. Brisco County Jr. (Bruce Campbell), and
4b. Ash (Bruce Campbell).
How's that?