Rachel wore her hair in a super short bob with heavy bang fringe for the premiere of "Che (Part 1)" at the Toronto International Film Festival in September 2008.

For the September 2009 premiere of "The Lucky Ones" Rachel pinned her short hair up in loose ringlets.

We think this bob was the real thing at "The Time Traveler's Wife" premiere in August 2009, but you never can tell with the Hollywood set.

Just four months later, McAdams debuted this long braided look at the premiere of "Sherlock Holmes" in the UK. Either she's got the hair-growing power of Superman, or this braid is an extension.

Is anyone else having "Friends" flashbacks? Rachel sported, uh, Rachel at the NYC premiere of "Morning Glory" in November 2010.