There are 5 Tremors movies:
Tremors
Tremors 2: Aftershocks
Tremors 3: Back to Perfection
Tremors 4: The Legend Begins
Tremors 5: Bloodlines
Tremors a collection of 5 films, which also spawned a short-lived television series, about huge deadly underground worms (Graboids) which hunt by sound and seize their prey with snakelike tongues. The original film starred Kevin Bacon and Fred Ward, though Michael Gross is the only cast member to have appeared in all four films, as well as the TV series.
Back in November last year, news broke that a new TV series is being developed based on the 1990 cult classic Tremors, with Kevin Bacon in the lead. He starred in the original as monster hunter Valentine McKee, and is coming back to both star in and executive produce the continuation of this popular horror franchise.
Unfortunately, we haven't heard anything further about this TV series since then. Thankfully, Kevin Bacon revealed recently that the project is still very much in development. It is being planned as a 10-episode mini-series. Read more at Movieweb.com.