Once again Jack Bauer, played by Kiefer Sutherland, has to foil terrorists and protect his family.

"Could the programme's clock-ticking plot be repeated without looking silly or stale?," asked BBC News Online reviewer Stephen Dowling.

But what do you think? Is series two as good as the first series? Is the format of the series beginning to grate?

This discussion is now closed but you can read what people thought below.

We might have seen it before but it's still better than anything else on television right now.
Simon Pople, UK

The start of series 2 was not as exiting as series 1, but there is just enough in the storyline to keep you interested.
Mo, UK

It's great to have it back - only problem is you want to watch every show in one go Lesley St Clair Compton, UK

To those who accuse 24 or flag-waving, what about the opening scene, a nasty torture sequence where the torturers are revealed to be US government? Not to mention Jack Bauer shooting a witness in the name of the greater good... it's refreshing to see a programmes speculating how it probably IS done when chips are down rather than how it should be in a perfect world.
Tim Gomersall, UK

Excellent apart from the daughter. As they missed the opportunity to kill her off in the first series, she should be parked somewhere out of harm's way and forgotten about...
Peter,

I did not see the first series and to be honest I watched it last night by accident but it was compelling. Sounds crude but I loved the fact that he shot that guy without any warning at all. To top that off he then asked for a hacksaw, call me callous but I do appreciate the unexpected in TV dramas.
Matthew, England

Seems like there are loads of beautiful blondes in the first part!
Roy Matthews, UK

I think series 2 will have to work hard to keep from repeating elements from series 1. I think it might have been wise to put Kim Bauer a bit further into the background this time to retain credibility.

The second series will have one major advantage over the first. We should get one complete story instead of two linked stories that the writers came up first time round. The show was nearly cancelled half way through its run and the writers ended the first story half way through the day!
Roy Matthews, UK

Good start to the second series but the real-time format didn't seem to work - between 8-9 Jack had visited Kim, went home and mooched around for a while, went back to work, was briefed about the bomb, had a suspect brought in for questioning, shot him, did whatever he did with the hacksaw and had a shower and a shave!
Rebecca, UK

Being a digital viewer - I'll probably still end up watching each episode twice. You find yourself with one eye on the clock not wishing it to end - Pure Class
Jassy, UK

I have just caught the first episode of the second series of 24. This was fantastic. I missed the first series but basically got the gist of the plot from reading updates and watching a few episodes but will definitely be sticking with this. Its the best thing on TV.
Paul Nelson, UK

I thought the first episode on Sunday night was a good start for a second series. It got right into it without having to reintroduce the characters to us. How ever I did feel that perhaps the story line has been set up to make it seem to Americans that the areas in the middle East outside of Israel are only sources of oil and terrorists.
Nigel, Scotland

Great first two episodes last night apart from the stupid daughter. There was no need to get her in on a subplot whatsoever, just get her out of the city and leave it there.
Andrew Robinson, UK

An excellent start, much more hard hitting, only another 23 weeks to go!
Dave - Dudley, UK

It's great to have it back - only problem is you want to watch every show in one go.
Lesley St Clair Compton, Hertfordshire

Might I point out that the idea behind 24 is far from original. In the 1950s, radio listeners listened each week to 26 Hours. This was a thriller, made, I think by the BBC. The adventures of agent Gregory George Athelstone Keane were told in real time. As I recall, it involved some sort of derring-do in occupied Berlin. How about a poke through the archives?
Dave Gittins, Australia

Although the real proof of the pudding will be in a few weeks time when the plot has developed a little more, I think the opening episode of the new series was well worth the wait. It is still well written, tense and engaging. Roll on next Sunday!
Simon W, England

Still the best...
Richard C, Croydon, England

Brilliant! I didn't see the first series, but heard such good reports that I tuned in specially to see the start of the second and was instantly hooked. Can't wait 'til next weeks episode!
Nick Ward, UK

It's an interesting program. Very entertaining and hugely addictive but also completely silly of course. It has a very unpleasant foundation of racism and seems to be essentially quasi-fascist propaganda.
Chu, UK

A second series was a risk but the plot resonates with a lot of current terrorist threats and is so far being portrayed in a credible way Chris Colville, England

They should have ditched Kim from the second series for a start. As welcome as the utterly gratuitous opening shot of her in her pants was, her plotline is only any good as comic relief. Still, gravelly-voiced widower Bauer is still the coolest guy on the screen (loved the witness "interrogation"), and the wedding subplot looks like fun. I particularly liked the closing shot of the first episode - Gillette should hire Kiefer immediately...
Paul Trueman, UK

The jury is out and deliberating. The first episode is no way as hard hitting as the first in the last series but I can't wait to see episode 3.
Rob Carlisle, UK - Yorkshire

A very promising start. A second series was a risk but the plot resonates with a lot of current terrorist threats and is so far being portrayed in a credible way. But with 23 hours to go this could change!
Chris Colville, England

It's almost as if the programme is propaganda for the US stance on Iraq. Except that the president is sensible enough to avoid involving the US war machine.
John, UK

I've been watching the new series of 24 in the USA and it's excellent...the first couple are a bit slow, but then it really gets going and is MUCH better than the first series...
Rhiannon, Belgium

A wicked way of spending Sunday evening Ru, England

I was sceptical, but I must admit the first episode has me hooked again. The format is still so good!
Joe, UK

To soon to give a accurate verdict but what I saw in episode 1 is very promising. I must admit series 1 had me hooked and I hope series 2 has the same twists and turns.
Robin Thorne, UK

I have been looking forward to the new series ever since the final series last year, in which I was absolutely engrossed. Last night's episode has set the stage for what will be a heavily plotted and exciting storyline, and a wicked way of spending Sunday evening.
Ru, England

Watched the first two episodes back-to-back last night (many thanks to the BBC for bringing it back to us). Was simply amazed, my heart rate was noticeably raised, and I wasn't disappointed. I only wish Kym had been killed along with Teri at the end of season one.
James, UK

Bang up-to-date storyline. Series 1 was attention grabbing. Episode 1 Series 2 continues this excellent format. The scene has been set for another action and tension packed rollercoaster!
Steve Jennings, Netherlands

The deft handling of so topical and emotive a theme is a joy and relief in equal measure to devoted 24 devotees - it could so easily have been flag-wavingly crass. Jack Bauer's return to the fray felt fresh and exciting, with new characters and familiar tensions galore. Roll on 09:00am!
Oliver James, London, UK

The acting is more wooden in series two. It's interesting to look at the contrast between the President Palmer and his staff, and those of President Bartlett in West Wing. 24's president is a patent amateur, advised by fools, in comparison to the consummate professional in West Wing. I'll still watch every minute of this series, though...
David Tonge, UK

Just watched the first two episodes of the new series and while it is pretty "samey" with reference to the first series, this is no bad thing as it looks as if this will be just as gripping. Problem is the waiting for the next hour. Any chance of showing it on a daily rather than weekly basis?
Sapna, UK

Nuclear terrorism - is this just some US propaganda for the war in Iraq? William, UK

I like it (so far). The characters have followed a logical progression and the multiple thread views seem to be tamed down which will make it more viewable. I think it is already more exciting than the first. The topic is a bit too 'God bless America' for my taste but they needed something big to warrant the need for everyone to pull another all-nighter.

But, please (!), no third series as the escalation in plotlines means Jack Bauer will be defending the US against an alien invasion!
Paul, Netherlands

Nuclear terrorism? Is this just some US propaganda for the war in Iraq?
William , UK

Fantastic. I was sceptical that a second series could replicate the brilliance of the first. But on this evidence we're all set for another great 24 hours.
Dan, UK

Fantastic yet again, It built up to a crescendo at the end of the programme leaving you hooked and wanting more.
Martin Regan, Bolton, England

I was addicted to the first series and, from the look of things, I will be stuck to BBC Two every Sunday. I even had a reason to watch BBC Three for the next episode. It was great.
Paul Campton, England

Hooked again instantly - I was hoping not to be Jonty Sexton - UK

I found the first series gripping but was disappointed that yet again the terrorist organisation has to be an Islamic one, though they didn't need to state the obvious, everyone came to the same conclusion - it's just sad to see that terrorist for all programs have to be Muslims. It's as though other terrorists don't exist. Other than that I can truthfully say it was gripping and I enjoyed it too.
Sabrina, United Kingdom

Hooked again instantly. I was hoping not to be, as I now have another 23 Sunday evenings stuck indoors.
Jonty Sexton, Old Portsmouth, UK

Definitely yes! The second series may not have the sheer number of twists and turns as the first series but it's still tense and exciting... just not as random. I guess this is what happens when you have enough budget for the whole series up front - more planning and intelligence then sheer wackiness.
David Scott, UK

Series 2 is same old same old. totally and utterly predictable - and interminable. 24 hours is 24 hours too long this time around...
Suzy Tawse, Australia

The producers are asking the viewer to defy belief for a second time and it doesn't really work Egons Pikelis, Latvia

I've been lucky enough to see up to episode 10. I definitely think it is better than the last series, with more twists and suspense, and some familiar faces returning.
Jamie Saunders, UK

I didn't see the first series, but I'm hooked on this one.
John B, UK

I have seen series 1 and part of series 2 in the USA. It is good, but not brilliant. Basically, the producers are asking the viewer to defy belief for a second time and it doesn't really work. They should have had a whole new cast for the second series.
Egons Pikelis, Latvia

In short, it can't (shouldn't) go on forever. I have been downloading it from America, and so far (Episode 12) series 2 is so much better than series 1. Note to Fox: Please don't run it till it gets stale.
Si, UK

Don't have digital so couldn't see the second episode, but the first one was very good at re-establishing where the characters are now and engrossing you in the new plot, it was left on two quite good cliff hangers (Kim and Jack) and am looking forward to next week.
Frazer Edwards, UK