by Clark Groome

The company of the Walnut Street Theatre’s production of “A Funny Thing Happened on the Way to the Forum,” Stephen Sondheim’s first solo musical, should probably change the coffee in the Green Room to decaf.

“Forum” is, in the right hands, a delight, a reminder of just how much fun a musical comedy can be. The Walnut’s production, which plays through Oct. 22, is in many ways appealing. A supporting cast that is, when left to its own devices, excellent, beautifully performs the smart and funny songs.

Central to the show is Pseudolus (Frank Ferrante), a slave who wants nothing more than to be free. To gain his freedom he connives to arrange for his master, the young Hero (Brandon O’Rourke), to marry Philia (Alanna J. Smith), the girl next door, a virgin courtesan promised to the famous warrior Miles Gloriosus (Nichalas L. Parker).

It’s all very complicated and often hilarious. The ultimate success of the production is in Pseudolus’ hands. At the Walnut, Frank Ferrante, best known for his impersonation of Groucho Marx, not only stars but also directs.

And this is where the decaf would be helpful. While the show has many slapstick and farcical moments, the whole business at the Walnut is so hyper that it ultimately calls more attention to the direction and the director/star than it does to the story and the wonderful score.

The supporting cast — which includes Ron Wisniski and Mary Martello as Hero’s parents Senex and Domina; Fran Prisco as Lycus, the owner of the house of courtesans; and Scott Greer as Senex and Domina’s slave Hysterium — is spot-on when Pseudolus isn’t around overacting, making unnecessary gestures to the audience and visibly cracking himself up.

It’s too bad because this kind of comedy works best when it’s played straight rather than being overdone.

Ferrante’s production benefits from the good designers Robert Andrew Kovach (set), Paul Black (lighting), Mary Folino (costumes) and Ed Chapman (sound). John Daniels directs the terrific musical aspects of the production.

In the Broadway revival of the show in 1996, Nathan Lane and later Whoopi Goldberg were Pseudolus. Both know how to balance the demands of a musical comedy that borders on farce. Too bad that Ferrante doesn't.

For tickets, call 215-574-3550 or visit www.walnutstreettheater.org