diff --git a/submixer.sh b/submixer.sh
index 6f00916..756bb8a 100755
--- a/submixer.sh
+++ b/submixer.sh
@@ -22,13 +22,13 @@ in1=$(mktemp --suffix ".ass")
 in2=$(mktemp --suffix ".ass")
 
 # Convert 1st srt to ass
-ffmpeg -i $1 $in1
+ffmpeg -i "$1" "$in1"
 
 # Convert 2nd srt to ass
-ffmpeg -i $2 $in2
+ffmpeg -i "$2" "$in2"
 
 # Write header
-cat <<< $HEADER > $OUTFILE
+cat <<< "$HEADER" > $OUTFILE
 
 # Get events from 1st input
 # awk is easier
@@ -37,7 +37,7 @@ awk '
     str = $0
     sub(/,Default,/, ",Top,", str)
     print str
-}' $in1 >> $OUTFILE
+}' "$in1" >> $OUTFILE
  
 # Get events from 2nd input
 # awk is easier
@@ -46,8 +46,8 @@ awk -v ORS="" '
     str = $0
     sub(/,Default,/, ",Bot,", str)
     print str
-}' $in2 >> $OUTFILE
+}' "$in2" >> $OUTFILE
 
 # cleanup
-rm $in1
-rm $in2
+rm "$in1"
+rm "$in2"