Shenae Grimes and Jessica Stroup's Joint Birthday Bash

Joining together for a weekend celebration, Shenae Grimes and Jessica Stroup held a joint birthday bash at Beacher's Madhouse at the Hollywood Roosevelt Hotel on Saturday night (October 23).

Presented by Samsung Galaxy S, the "90210" hotties were treated to a vaudeville-esque fete at which guests were strongly encouraged to dress the part in theatrical attire.

A GossipCenter source tells that both girls, in full costume, were in great spirits and spent the evening dancing and catching up with friends.

At one point, David Arquette (who co-owns Beacher's) led the crowd in singing "Happy Birthday" as Shenae and Jessica were presented with a giant birthday cake along with a few other small gifts.

Also in attendance for the event were Brittany Snow, Paris and Nicky Hilton, Brandon Davis, and fellow "90210" co-stars AnnaLynne McCord, Ryan Eggold, Trevor Donovan and Michael Steger.

Enjoy the pictures of Shenae Grimes and Jessica Stroup at their joint birthday bash (October 23).