An official opening is set for Oct. 9. The production, to be directed by Greg MacKellen, will also feature Michael Rhone as Hysterium, Luke Chapman as Hero, Megan Ihle as Philia, Bob Greene as Senex, Chris Macomber as Domina, Rudy Guerrero as Marcus Lycus and Rob Hatzenbeller as Miles Gloriosus.

Elmer Strasser, Kate Paul, Christine Bagube, Janine Burgener, Isaiah Boyd, Jack Sale and Tyler Costin will form the ensemble.

Dave Dobrusky will provide musical direction, and Tom Segal will choreograph. Louise Jarmilowicz will provide costumes, and Ellen Brooks will do the lighting.

Cavanagh has also appeared in the films "Robin Hood: Men in Tights," "For Richer or Poorer" and "Jimmy Neutron: Boy Genius" and on television in "Exes & Oh’s" and "The Mighty B!" She has appeared in Moon productions of Jubilee, High Spirits and Out of This World.

…Forum, featuring a score by Stephen Sondheim and a book by Larry Gelbart and Burt Shevelove, is a farcical tale of Pseudolus' efforts to help his young master, Hero, win a young courtesan-in-training, and his own freedom in the process. Songs from the classic score include "Comedy Tonight," "Everybody Ought to Have a Maid," "Lovely," "Free," "Pretty Little Picture" and "That Dirty Old Man." The Moon's production is partly presented in honor of Sondheim's 80th birthday this year. The Moon has also announced that Tony Award nominee Rebecca Luker will appear in its Oct. 28 "Salon Evening," a tribute to composer Jerome Kern. The acclaimed soprano "will join a group of Moon singers to offer Kern classics like 'All the Things You Are,' 'The Song is You,' 'I’ve Told Every Little Star,' 'The Way You Look Tonight, and 'I Won’t Dance,' as well as rarely-heard gems," according to press notes.

The Eureka Theatre is located at 215 Jackson Street in San Francisco. For tickets, call (415) 255-8207 or visit 42ndstreetmoon.org.