Roger Rees will replace Nathan Lane in “The Addams Family” next spring, joining fellow “Cheers” alum Bebe Neuwirth in the large-scale Broadway tuner.

Replacement of co-topliner Lane is a delicate matter for “Addams Family,” which proved a B.O. powerhouse when it began previews March 8. Lane is generally thought to be a considerable draw for Broadway musicals, and although critical reception to “Addams” was largely harsh, Lane’s perf was almost universally singled out for praise.

One indicator of Lane’s importance to the B.O. power of “Addams”: When the thesp took a skedded week off in late August, sales for the frame plummeted by a third compared to the prior sesh, falling from $1.1 million to $765,000. The week he returned, receipts once again topped the $1 million mark.

When Neuwirth took her vacation this fall, weekly sales slipped by 14%.

Still, the “Addams” title itself remains a commercial force. And thesps familiar from TV have proven big B.O. draws in the past, with Sean Hayes’ toplining gig in “Promises, Promises” helping to drive robust sales at that revival.

“Addams” consistently held a spot in the Rialto’s millionaires’ club up until the end of the summer; since then, receipts have sometimes dipped below the $1 million mark.

Rees and Neuwirth have collaborated onstage before, most recently in an Off Broadway revue of Kurt Weill tunes, “Here Lies Jenny,” in which Rees directed Neuwirth. Pair also appeared together in a 1999 production of “The Taming of the Shrew” at the Williamstown Theater Festival, as well as in “Cabaret Verboten” at L.A.’s Center Theater Group.

In “Addams,” Rees will play family patriarch Gomez opposite Neuwirth’s Morticia.

Lane exits “Addams” March 6, with Rees set to join the cast March 22.