The members of Led Zeppelin are getting serious about a plagiarism lawsuit over their Stairway To Heaven hit by hiring top entertainment lawyer Helene Freeman to represent them.

Freeman, who litigated a series of victories for Justin Timberlake's former boy band 'N Sync, has signed on to defend Jimmy Page, Robert Plant and John Paul Jones in a copyright infringement claim filed by a lawyer representing late Spirit guitarist Randy California.

Francis Malofiy filed a complaint in May (14), arguing that the opening notes of Stairway To Heaven are too similar to notes from a song written by his late client's 1968 song Taurus - and that California deserves credit for at least inspiring the track.

Page dismissed the lawsuit as "ridiculous", but it appears he's taking it seriously - and now Freeman has until 22 September (14) to answer the late California's claims via his estate attorney.