Maggie is, undoubtedly, best known for her role in the hugely successful, yet still very
 much "culty", Australian prison drama Prisoner. The series, which originally ran from
 1979 to 1987, was known outside of Australia as Prisoner: Cell Block H. This to eliminate
 confusion with the, similarly titled, British 60s drama The Prisoner. Prisoner catapulted 
many of the actresses who appeared in it to global fame when it was subsequently broadcast 
in many countries years after production actually ceased.

Maggie joined the series in 1982 after being spotted in The Pirate Movie by
 the producers of Prisoner. Her character, soon to become perhaps the show's best 
known and the one viewers loved-to-hate, Joan 'The Freak' Ferguson, entered 
in episode 287 and remained until the final show, over 400 episodes later.

It's not unfair to say that Joan Ferguson had few redeeming qualities but
 the role was a gift for an actress. The complex character of 'The Freak'
 was brought to life by Maggie's portrayal, tackling violence, corruption, 
lesbianism, death, loneliness, blackmail, drugs, "motherhood", hatred, and
 pure unadulterated, downright evil in those five memorable years 'inside'.

1. Maggie as Joan 'The Freak' Ferguson, 2. Joan and Rita Connors get to grips, 3. Betty Bobbit,
 (Judy Bryant), Maggie, and Jane Clifton (Margo Gaffney) at Prisoner's 400th episode party,
 4. Maggie, Patsy King, Val Lehman, and Sheila Florance celebrate the success of Prisoner with
 some of that (in)famous "grog", 5. September 1986 - Having filmed the final scenes on episode
 692, the Prisoner gang pose for the final time. The gates have shut down on Wentworth Detention
 Centre forever, 6. Joan and Rita "have words" yet again, 7. Freaky Realistic - Joan Ferguson takes
 no prisoners!, 8. Maggie welcomes Sammy Davis Jnr. to Wentworth.