According to a report at Variety, Farrell is currently in negotiations to play one of the titular characters in the film, though it's unknown whether he'll be playing King Arthur or his knight Lancelot.  In the next year, Farrell will be starring in the remake of Total Recall from director Len Wiseman, as well as Seven Psychopoaths, which reunites him with In Bruges writer-director Martin McDonagh.

Dobkin's Arthur & Lancelot was purchased as a spec script for $2 million, superseding two other potential Arthurian projects in development at Warner Bros.  The film was dated for March 15, 2013. Dobkin cast Kit Harington from HBO's Game of Thrones and Joel Kinnaman of AMC's The Killing as his two leads.  Everything appeared full-steam ahead until December of last year.

That's when the studio started getting cold feet.  Originally budgeted at $90 million, the production costs were reportedly creeping upwards, potentially costing as much as $130 million.  Without globally-recognizable lead actors, that's a big price tag in the newly risk-averse studio blockbuster game.  At the time, Warner Bros wouldn't proceed unless costs could be controlled and was said to have invited Dobkin to shop the project to other studios. 

In January, pre-production was put completely on hold in order to get the budget properly sorted out.  That was the last we heard and it certainly didn't bode well.  When Kinnaman was cast as the lead in the Robocop remake last month, it wasn't unreasonable to assume that Arthur & Lancelot wouldn't be happening.

It looks like Dobkin and his creative team have managed to wrangle the budget down.  Not only that, but in Colin Farrell they've found an actor with the profile to assuage the studio's fears about going with relative unknowns.