Edward Herrmann and Frances Conroy have joined the cast of the Mark Taper production of Neil Simon's latest, The Dinner Party, director John Rando told Playbill On-Line. Already in the cast are John Ritter, Henry Winkler and Veanne Cox.

The Dinner Party is set to premiere at the Mark Taper Forum Dec. 2. A comedy set in a chic restaurant in Paris, it deals with six guests who are confronted with strange surprises from their past.

Theatre veteran Herrmann has starred in such recent New York productions as John Patrick Shanley's Psychopathia Sexualis and Terrence Rattigan's The Deep Blue Sea. Conroy was last seen on Broadway in Ring Round the Moon. Other recent work includes The Ride Down Mt. Morgan at the Public Theater and The Little Foxes at Lincoln Center Theater.

Ritter is best known for his television work in such series as "Three's Company" and "Hooperman." Winkler, too, is a well-known television actor, having created the role of the Fonz on "Happy Days." Cox is more of a theatre presence, having appeared frequently on the New York stage in recent years, in such plays as Company, The Waiting Room and The Food Chain.

* Three world premieres and three West Coast premieres have been scheduled by the Mark Taper Forum for its upcoming 1999-2000 season, the theatre's 33rd.

Returning to the Taper are playwrights Simon, Peter Parnell and Lisa Loomer, who will be joined by writers new to the Taper stage: August Wilson, Tina Landau and Robert Glaudini.

The 1999-2000 season will commence Oct. 7 with Landau's Space, a play which follows a brilliant and famous neuro-surgeon who has suddenly become a magnet for patients claiming to be alien abductees.

Simon's The Dinner Party will follow on Dec. 2. Simon has had 15 plays produced by either the Taper or its sister company, the Ahmanson.

The West Coast premiere of Wilson's Jitney will be presented Feb. 3, 2000. The story deals with cab drivers in Pittsburgh in the late 70s. The play had its premiere in that city two years ago.

Parnell, whose Cider House Rules was seen a year ago at the Taper, will be represented by the world premiere of Tuva or Bust, which he adapted from Ralph Leighton's book of the same name. It deals with the adventures of the colorful, eccentric physics professor Richard Feynman, who will be portrayed by Alan Alda. April 26.

The fifth play in the season will be the world premiere of The Poison Tree by Robert Glaudini, which was commissioned by the Taper and developed in workshop productions. A company spokesperson described it as "a fascinating play of poetry and seduction that echoes real events in southern California." June 8.

Loomer, last seen at the Taper with The Waiting Room, will offer her latest play Expecting Isabel Aug. 3 in a West Coast premiere. The play recently won the American Theatre Critics Association best play award. It's a satire about a couple of yuppies trying to have a baby.

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