Pictures of Jennifer Garner, Russell Brand, Helen Mirren at Arthur Premiere in NYC

The cast of Arthur matched in muted hues at their NYC premiere last night. Jennifer wore Oscar de la Renta and was coming straight from Letterman while her girls enjoyed the California sunshine with Grandma Affleck. On the red carpet she talked about being nervous when filming atop a huge horse and says she hopes she doesn't disappoint fans when she takes on the role of Miss Marple — check out PopSugar Rush for more from Jennifer! Russell Brand revealed that there may not be truth to his Rock of Ages casting rumors, since he would like to be able to spend more time with wife Katy Perry. She couldn't join Russell for the premiere, though she did tweet her support from Scotland where she performed last night. Similar to his character, Russell told us falling in love made him grow up, but last night it was all about his female costars. He gushed about Helen Mirren, who, along with the rest of her costars including Greta Gerwig also got lots praise from director Jason Winer during Buzz's sit-down interview. Today Jennifer is stopping by Regis and Kelly as well as Late Night With Jimmy Fallon to promote their movie ahead of its Friday release.