custom nemo actions / bash script

i am trying to add a custom action to the nemo file manager. The purpose of the action is just to replace all whitespace in the filename by "_". My action file looks like this: [Nemo Action] Name=Normalize Comment=replace all occurences of " " by "_" Exec= Selection=Any Extensions=Any The bash script normalize.sh is i the actions directory and looks like this: #!/usr/bin/bash if [[ "$#" != 1 ]] then exit 1 fi name=echo "$1" | sed "s/\ /\_/g" mv "$1" "$name" exit 0 Does anybody know, why this isn't working?