As if the exploits of the four main protagonists weren't enough, there are also drunken cameo appearances from
their famous drinking buddies, most notably Lee Marvin, Robert Mitchum and Keith Moon.
«Happy Christmas» also features Mark Webber and — naturally — Lena Dunham, filling out a cast of rather
famous faces, much more in line with «
Drinking Buddies» than the director's earlier, lower - profile films.