Ben 10 - Season 3 - Eps 13: The Visitor
While snowmobiling, two guys accidentally release an alien named Xylene from a strange container. At a park, Ben (as Wildmutt) steals Gwen's kite, so she casts a spell to make dogs attracted to him. Grandpa Max seems sad to be in St. Louis since it is where he met his wife. Xylene attacks, and Grandpa Max comes to defend, only to recognize her. Xylene reveals that she came to find the Omnitrix since she lost it when Vilgax attacked her ship. While Grandpa Max and Xylene talk about the past, a robot emerges from the area where Xylene was and attacks Ben and Gwen. The mechadroid attacks twice, taking Grandpa Max with him. Now Ben must work with Xylene (to his dismay) to save Grandpa Max.
About Ben 10

Title: Ben 10
First Air Date: 2005-12-27
Last Air Date: 2008-04-15
Status: Ended
Rating: 8.152/10 (from 1655 votes)
Language: EN
Seasons: 5
Total Episodes: 52
Network: Cartoon Network
Genres: Animation, Sci-Fi & Fantasy, Action & Adventure, Comedy, Kids
Production Companies: Cartoon Network Studios, Man of Action Entertainment
Synopsis
When 10-year-old Ben Tennyson discovers a mysterious device, he gains the power to change into ten different alien heroes, each with uniquely awesome powers. With such abilities at his disposal, Ben realizes a greater responsibility to help others and stop evildoers, but that doesn't mean he's above a little superpowered mischief now and then.
Cast

Tara Strong
Ben Tennyson (voice)

Meagan Moore
Gwen Tennyson (voice)

Paul Eiding
Grandpa Max (voice)