The first half of the Venture Bros.' fourth season might be subtitled The Venture Bros. Grow Up, since so much change is afoot for the hapless Hank and Dean Venture, their scientist dad Rusty, and bloodthirsty bodyguard Brock Samson; naturally, most of these formative moments are utter disasters, as befits the Venture family, and all of it delivered in the most inventive and frequently hilarious ways. Season 4 opens with the Venture compound under assault and Samson (voiced by Patrick Warburton) out of commission due to an explosion; Samson eventually rejoins his old outfit, the G.I. Joe-esque Sphinx, which requires the reformed arch-villain Sgt. Hatred (voiced by Christopher McCulloch, a.k.a. series cocreator Jackson Publick) to step in and mind the boys. Meanwhile, Dean (Michael Sinterniklaas) is reluctantly groomed by his father (James Urbaniak) for a life in super-science, and Hank (McCulloch) searches for a father figure to replace Brock. Candidates include Hatred and Captain Sunshine (Batman regular Kevin Conroy), whose interest in Hank is decidedly prurient. There are also surprises afoot for necromancer Dr. Orpheus (Steven Rattazzi) and daughter Triana (Lisa Hammer), as well as the Monarch's Henchman, 21 (cocreator Doc Hammer), and the rise of the delusional Phantom Limb (Urbaniak) as a threat to the Ventures. Venture vets will revel in the razor-sharp dialogue, the skewering of pop-culture sacred cows, and the terrific vocal performances by every member of the cast, with Urbaniak, Rattazzi, and McCulloch as standouts. Extras include witty, informative commentary by Publick and Doc Hammer on every episode, as well as a battery of deleted scenes and a very amusing abandoned cold opening that finds 21 ruining the Monarch's mock invasion of the Venture compound.