did he act in any film?
Yes,  "Bikini Bandits" and its sequel.
Maynard James Keenan
 He also appeared as Satan in the 2002 film "Bikini Bandits" and its 2004 sequel "Bikini Bandits 2: Golden Rod".
what is tool? American rock band when did this band form? 1990 who are the members of this band? Danny Carey, Adam Jones and Maynard James Keenan what kind of music is associated with this band? Rock who is the lead singer of this band? Maynard James Keenan where is he from? Ravenna, Ohio did he belong to any other band before joining the former one? Yes, TexA.N.S. what else did he do apart from singing? Comedy and acting
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Maynard James Keenan [SEP] Comedy and acting
On April 1, 2005, the official Tool website announced, as an April Fools' Day prank, that "Maynard has found Jesus" and would be abandoning the recording of the new album temporarily and possibly permanently. Kurt Loder of MTV contacted Keenan via email to ask for a confirmation and received a nonchalant confirmation. When Loder asked again, Keenan's response was simply "heh heh". On April 7, the official site revealed that it was a hoax. During an interview Keenan later stated, "It was April Fools'. If you fall for that on April Fools' Day, there's nothing I can do for you." He has been part of other April Fools' pranks related to Tool, including one in which he was said to be in critical condition after a tour bus accident.