The clown incursion began as a stealth operation, first with one and then another peering tentatively out at us from the wings. Intermission music was still playing, and the audience still milling, as the clowns assembled, until gradually a whole pack of them (a gaggle? a murder? a herd?) stood at the lip of the stage, gazing quizzically at us.

They looked so shy, so endearingly perplexed in their green overcoats and silly moth-eaten caps, the long earflaps out at an angle, as if the air had lofted them mid-flight. Surely these are harmless creatures, no? Surely if one of the clowns in “Slava’s Snowshow” should appear silently at your side, wanting to climb into the crowd and surf the seat backs, the decent thing to do is offer a hand?

That’s what I did, and others also did, and soon clowns were everywhere, agents of a joyous anarchy. In their innocence, the clowns were like small children, and we responded to them with fond indulgence. They clambered over the audience, they sprayed us with water — and we rooted for their triumph.

A note to the clown-averse, who are legion, and to those who shudder at the thought of an interactive experience like “Slava’s Snowshow,” which opened on Thursday night at the Stephen Sondheim Theater: I did not expect to like it, let alone love it, as I did. Eons ago, when I saw “Slava’s Snowshow” Off Broadway at the Union Square Theater, I bristled all the way through. I even hated the famous blizzard at the end.