- Directors: Brad Silberling
- Producers: Sid and Marty Krofft, Jimmy Miller
- Writers: Chris Henchy, Dennis McNicholas, Television Series, Sid and Marty Krofft
- Genres: Adventure, Comedy, Sci-Fi
- Actors: Will Ferrell, Anna Friel, Danny McBride, Jorma Taccone
Three years after being kicked out of the science department for his theory of time warps, and his attempt on Matt Lauer’s life, Rick Marshall is reduced to working as a teacher at the George C. Page Museum until he meets Holly Cantrell whose finding urges him to create a tachyon amplifier to enable time warp travel. They go to the Devils Cave attraction where the finding was found, hiring its tour guide Will Stanton. But once they’ve activated the tachyon amplifier, losing it in the process, the three end up in a parallel universe where all timelines converge. They soon meet some ape men, Pakuni, two of whom were going to kill the younger one, when Stanton unintentionally gives the other two the secret of fire as they run off. The gang then proceed to help the other one, named Cha-Ka, until he runs off with them in pursuit.
Once catching up to Cha-Ka, they are trapped by a tree which turns out to be a dinosaur feeding site, being attacked by a Tyrannosaurus. The T. rex chases them until they come to a small land bridge. Marshall is convinced they are safe as he explains how a T. rex has a walnut-sized brain, and is incapable of judging depth and distance. Hearing this as he stalks away, the T. rex stops in his tracks, turns, and runs full speed to jump across the chasm. Chasing them until they reach a crevice in a cave, it gives up, though still wanting to eat Marshall. Holly, knowing the dinosaur’s attitude, gives him the name “Grumpy”. Though Marshall didn’t believe it to be possible, Grumpy’s vendetta becomes more apparent when he leaves a gify, beach-ball sized walnut, gift-wrapped.
Back on Earth, Matt Lauer reluctantly gives a second interview with Marshall this time proven right and proceeds to rub it in Matt Lauer’s face by bringing a dinosaur egg back and giving him a signed copy of his new book. But after being forced to show off the title of Marshall’s new book, Matt Lauer Can Suck It, history repeats itself with Matt trying to kill Marshall. Soon after the show ended, unaware of what Marshall and she left behind on the set, the dinosaur egg Holly found hatches into a baby Sleestak.