diff --git a/src/t_zset.c b/src/t_zset.c
index 50ad8d43..4812709e 100644
--- a/src/t_zset.c
+++ b/src/t_zset.c
@@ -1259,10 +1259,11 @@ int zuiNext(zsetopsrc *op, zsetopval *val) {
     if (op->type == REDIS_SET) {
         iterset *it = &op->iter.set;
         if (op->encoding == REDIS_ENCODING_INTSET) {
-            int64_t ell = val->ell;
+            int64_t ell;
 
             if (!intsetGet(it->is.is,it->is.ii,&ell))
                 return 0;
+            val->ell = ell;
             val->score = 1.0;
 
             /* Move to next element. */
diff --git a/tests/unit/type/zset.tcl b/tests/unit/type/zset.tcl
index bab98854..806f4c88 100644
--- a/tests/unit/type/zset.tcl
+++ b/tests/unit/type/zset.tcl
@@ -524,6 +524,14 @@ start_server {tags {"zset"}} {
         r zrange out 0 -1 withscores
     } {neginf 0}
 
+    test {ZINTERSTORE #516 regression, mixed sets and ziplist zsets} {
+        r sadd one 100 101 102 103
+        r sadd two 100 200 201 202
+        r zadd three 1 500 1 501 1 502 1 503 1 100
+        r zinterstore to_here 3 one two three WEIGHTS 0 0 1
+        r zrange to_here 0 -1
+    } {100}
+
     proc stressers {encoding} {
         if {$encoding == "ziplist"} {
             # Little extra to allow proper fuzzing in the sorting stresser