diff --git a/sent.c b/sent.c
index c50a572..9534fca 100644
--- a/sent.c
+++ b/sent.c
@@ -428,6 +428,10 @@ load(FILE *fp)
 		maxlines = 0;
 		memset((s = &slides[slidecount]), 0, sizeof(Slide));
 		do {
+			/* if there's a leading null, we can't do blen-1 */
+			if (buf[0] == '\0')
+				continue;
+
 			if (buf[0] == '#')
 				continue;